Channel estimation for wireless communication network

ABSTRACT

There is disclosed a method of operating a receiving radio node in a wireless communication network, the method including performing channel estimation based on received signaling, the channel estimation providing a channel estimate value for each subcarrier of a set of subcarriers. The received signaling covers a number NPRB of Physical Resource Blocks, PRB, in frequency domain, each PRB having a number NSC of subcarriers. The set of subcarriers has a number NSUB of subsets of subcarriers, subcarriers of the same subset being associated to the same PRB of the number NPRB of PRBs. The channel estimation associates different channel estimate values to different subcarriers of one or more of the NSUB subsets. The disclosure also pertains to related devices and methods.

TECHNICAL FIELD

This disclosure pertains to wireless communication technology, inparticular for high frequencies.

BACKGROUND

For future wireless communication systems, use of higher frequencies isconsidered, which allows large bandwidths to be used for communication.However, use of such higher frequencies brings new problems, for exampleregarding physical properties and timing. Ubiquitous or almostubiquitous use of beamforming and/or the use of multiple TRPs havingsimultaneous communication links with one wireless device, with oftencomparatively small beams, may provide additional complications thatneed to be addressed.

SUMMARY

It is an object of this disclosure to provide improved approaches ofhandling wireless communication, in particular regarding channelestimation. The approaches described are particularly suitable formillimeter wave communication, in particular for radio carrierfrequencies around and/or above 52.6 GHz, which may be considered highradio frequencies (high frequency) and/or millimeter waves. The carrierfrequency/ies may be between 52.6 and 140 GHz, e.g. with a lower borderbetween 52.6, 55, 60, 71 GHz and/or a higher border between 71, 72, 90,114, 140 GHz or higher, in particular between 55 and 90 GHz, or between60 and 72 GHz; however, higher frequencies may be considered, inparticular frequency of 71 GHz or 72 GHz or above, and/or 100 GHz orabove, and/or 140 GHz or above. The carrier frequency may in particularrefer to a center frequency or maximum frequency of the carrier. Theradio nodes and/or network described herein may operate in wideband,e.g. with a carrier bandwidth of 1 GHz or more, or 2 GHz or more, oreven larger, e.g. up to 8 GHz; the scheduled or allocated bandwidth maybe the carrier bandwidth, or be smaller, e.g. depending on channeland/or procedure. In some cases, operation may be based on an OFDMwaveform or a SC-FDM (also referred to as DFT-s-waveform), for examplefor downlink and/or uplink, in particular a FDF-SC-FDM-based waveform.However, operation based on a single carrier waveform, e.g. SC-FDE(which may be pulse-shaped or Frequency Domain Filtered, e.g. based onmodulation scheme and/or MCS), may be considered for downlink and/oruplink. In general, different waveforms may be used for differentcommunication directions.

Communicating using or utilising a carrier and/or beam may correspond tooperating using or utilising the carrier and/or beam, and/or maycomprise transmitting on the carrier and/or beam and/or receiving on thecarrier and/or beam. Operation may be based on and/or associated to anumerology, which may indicate a subcarrier spacing and/or duration ofan allocation unit and/or an equivalent thereof, e.g., in comparison toan OFDM based system. A subcarrier spacing or equivalent frequencyinterval may for example correspond to 960 kHZ, or 1920 kHz, e.g.representing the bandwidth of a subcarrier or equivalent.

The approaches are particularly advantageously implemented in a future6^(th) Generation (6G) telecommunication network or 6G radio accesstechnology or network (RAT/RAN), in particular according to 3GPP (3^(rd)Generation Partnership Project, a standardisation organization). Asuitable RAN may in particular be a RAN according to NR, for examplerelease 17 or later, or LTE Evolution. However, the approaches may alsobe used with other RAT, for example future 5.5G systems or IEEE basedsystems.

It may be considered that the RAN and/or a radio node is operating in anunlicensed frequency band (or carrier or part thereof, also referred toas license-exempt) and/or based on a LBT or channel assessment procedureto access (for transmission) the frequency band (or carrier or partthereof), for example in a License Assisted Access (LAA) operation modeand/or in the context of NR-U (NR unlicensed).

There is disclosed a method of operating a receiving radio node in awireless communication network. The method comprises performing channelestimation based on received signaling. The channel estimation providesa channel estimate value for each subcarrier of a set of subcarriers.The received signaling covers a number NPRB of Physical Resource Blocks,PRB, in frequency domain, each PRB having a number NSC of subcarriers.The set of subcarriers comprises a number NSUB of subsets ofsubcarriers, subcarriers of the same subset being associated to the samePRB of the number NPRB of PRBs. The channel estimation associatesdifferent channel estimate values to different subcarriers of one ormore of the NSUB subsets.

A receiving radio node for a wireless communication network isdescribed. The receiving radio node is adapted for performing channelestimation based on received signaling. The channel estimation providesa channel estimate value for each subcarrier of a set of subcarriers.The received signaling covers a number NPRB of Physical Resource Blocks,PRB, in frequency domain, each PRB having a number NSC of subcarriers.The set of subcarriers comprises a number NSUB of subsets ofsubcarriers, subcarriers of the same subset being associated to the samePRB of the number NPRB of PRBs. The channel estimation associatesdifferent channel estimate values to different subcarriers of one ormore of the NSUB subsets.

The approaches described herein facilitate reliable channel estimationin particular for high frequency networks, accommodation for large SCSand/or frequency variable channels.

The received signaling may be and/or comprise data signaling or controlsignaling and/or communication signaling; it may be considered that thereceived signaling comprises reference signaling, which may beassociated to data signaling or control signaling. In general,performing channel estimation may pertain to measuring signaling onspecific REs or SCs (Resource Elements or SubCarriers), e.g. signalingaccording to a signaling sequence (e.g., modulation symbol sequence),which may be mapped to REs and/or SCs, for example according to aconfiguration and/or allocation. The receiving radio node may be assumedto know (e.g., due to configuration and/or allocation and/or scheduling)the sequence and/or mapping (e.g., according to a comb, and/or such thatnot all REs or SC of one symbol or allocation unit may be expected tocarry the signaling to be measured) and/or transmission characteristicsof the signaling to be measured. The received signaling may be referredto as first signaling. The received signaling may be signaling on aPDSCH or PDCCH (e.g., if the receiving radio node is a UE or wirelessdevice) or a PUCCH or PUSCH (e.g., of the receiving radio node is anetwork node), or a PSSCH or PSCCH (e.g., in a sidelink scenario).

In general, the method may comprise, and/or the receiving radio node maybe adapted for, communicating based on the channel estimation.Communicating based on the channel estimation may comprise demodulationand/or decoding data signaling and/or control signaling of the receivedsignaling, and/or determining and/or transmitting a measurement reportbased on the channel estimation, and/or transmitting (second signaling)in response to, and/or based on the channel estimation, e.g. performinglink adaptation and/or power control (e.g., for the transmitting radionode, e.g., with control signaling, or for the receiving radio node,e.g. adapting transmission power for subsequent transmission) based onthe channel estimation.

The channel estimation may be represented by a plurality of channelestimate values, which may pertain to different subcarriers and/orgroups of subcarriers; such a group may comprise subcarriers of the samePRB in a subset, and/or subcarriers with a channel estimate and/or emptyof a channel estimate (a channel estimate value may be assigned orassociated to such SC). A channel estimate value may be considered to beassociated to a SC if the value is provided and/or mapped and/ordetermined for the SC; e.g. based on measurement performed on or forother SC. The channel estimation may associate different channelestimate values to different subcarriers of one or more of the NSUBsubsets, e.g. such that for subcarriers in the same subset, there may beassociated different values to two or more SC, and/or for SC associatedto the same PRB there may be associated different values. For example.SC of the same subset may have the same value associated, but for SC ofdifferent subsets associated to the same PRB there may be differentvalues associated. In general, different subsets may have different SC,and/or may be non-overlapping. Subset associated to the same PRB mayhave SC of this PRB. The union of subsets associated to the same PRB maycomprise all SC of the PRB.

NPRB may correspond to an integer number, e.g. 1 or larger. NSC may be12, e.g. according to NR specifications, or different, e.g. 14 or 16 or13, e.g. for other network technology. A PRB may represent a range ofsubcarriers allocatable for signaling. In general, the receivedsignaling may cover and/or be transmitted on and/or be associated to anallocated or configured or scheduled frequency range, e.g. according toa frequency allocation, which may correspond to the set of subcarriersand/or the number NPRB of PRBs. The received signaling may cover one ormore allocation unit and/or symbols in time domain; the channelestimation in general may be applicable and/or used for communicating inthe allocation unit or symbol the signaling used to determine thechannel estimation was received on, and/or for later or earlier symbolsor allocation units carrying signaling, e.g. the received signaling, orother signaling.

NSUB may be based on a number of subsets NSP per PRB. In general, thenumber of subsets per PRB may be larger than 1. The number ofsubcarriers per subset may be an integer number and/or may be largerthan 1. A subset may comprise a plurality of subcarriers associated tothe same PRB and/or a plurality of subcarriers associated to differentPRBs. To each PRB, there may be associated a plurality of subsets, e.g.the same number of subsets per PRB. The subcarriers of a subset may becontiguous and/or neighbouring in frequency domain.

It may be considered that a channel estimate value associated to asubcarrier may be based on processing over a number NRANGE ofsubcarriers of same subset of NSC or lower, in particular such thatNSC/NRANGE=1, e.g. with I being an integer, for example I=2, 3 or 4 orlarger; it may be considered that NRANGE is an integer, in particular anodd integer larger than 1. The number of SC processed over may includethe subcarrier to which the channel estimate value is associated; insome cases, processing may comprise omitting this SC; e.g. if it isempty of a channel estimate of its own. In general, it may be consideredthat each channel estimate value associated to a subcarrier may be basedon at least 2, or at least 3, SC carrying a channel estimate (and/orassociated signaling). Thus, errors and deviations may be smoothed out.

It may be considered that a channel estimate value associated to asubcarrier may be based on a filter applied to an environment of thesubcarrier, wherein the environment may have a size of NRANGEsubcarriers, which may comprise the subcarrier to which the value isassociated. An environment may comprise one or more subcarriers belowand/or above in frequency domain; the number of SC below and above maybe the same, or different. Thus, appropriate filtering may be used.NRANGE or the number of SCs in the environment may comprise thesubcarrier to which the value is associated, or not.

In some cases, it may be considered that a channel estimate valueassociated to a subcarrier may be based on averaging and/or weighingover an environment of the subcarrier, wherein the environment may havesize of NRANGE subcarriers. Weighing may comprise and/or representperforming weighed filtering and/or weighted averaging, and/or omittingSC empty of a channel estimate.

In general, it may be considered that the number of subcarriersassociated to the same PRB in a subset is smaller than NSC, inparticular equal to or smaller than NSC/2 or NSC/3 or NSC/4; the numbermay be larger than 1. Thus, strong frequency variation may beaccommodated.

It may be considered that channel estimation may be based on measurementon received signaling, in particular determining a signal strengthand/or signal quality, e.g. SINR or SIR or EPRE (Energy per RE) and/orRSRP and/or received power or received energy; the measurement may berepresented or performed for a subcarrier, e.g. to provide a channelestimate for a subcarrier. There may be SC without channel estimatedetermined based on signaling carried on the subcarrier, e.g. due tosuch signaling not being transmitted and/or scheduled and/or configuredfor such SC; such SCs may be referred to as empty of a channel estimate.Thus, different signaling formats for measurements may be accommodated.

It may be considered that the channel estimation, in particular thenumber of subcarriers associated to the same PRB in a subset, may bedependent on the carrier and/or carrier frequency and/or bandwidthand/or bandwidth part and/or numerology and/or signaling characteristicassociated to the received signaling. For example, for higher carrierfrequencies and/or SCS, there may be used more subsets per PRB than forlower; e.g. for 960 kHz or higher SCS, there may be more subsets per PRBthan for 480 kHz or 120 kHz or lower, and/or for 480 kHz SCS there maybe more subsets per PRB than for 120 kHz SCS or lower.

In general, processing (e.g., averaging or weighing or filtering) over arange of subcarriers may comprise weighing one or more or allsubcarriers in the range not carrying a channel estimate (or empty of achannel estimate) with zero and/or disregarding or omitting such.Accordingly, the channel estimation may be based on actual expectedsignaling to be measured. Normalization may be performed accordingly.This may be dependent, e.g. on a configuration or allocation for thesignaling to be measured on (which may be comprised in the receivedsignaling), e.g. depending on the comb size used for the signaling, e.g.DMRS comb or reference signaling comb, or interlace or interleavingused.

In general, there may be considered determining the channel estimationfilter length that depends on the subcarrier spacing for use with afiltering solution that filters channel estimates from differentsubcarriers (if applied in frequency domain) and/or from different OFDMsymbols (if applied in time domain) to improve channel estimation. Afilter length may cover an integer number of subcarriers (SC); cases, inwhich a frequency range is covered that corresponds to a non-integernumber may be considered.

In general, filter length in the frequency domain or range may beinversely proportional to the sub-carrier spacing and/or proportional tothe coherence bandwidth of the channel.

In some cases, the filter length in the time domain may be proportionalto the sub-carrier spacing and/or inversely proportional to a Dopplerspread of the channel (and/or a speed or velocity of receiving radionode and/or between transmitter and receiver).

Instead of calculating a filter length, it may be considered calculatinga number of subcarriers (if applied in frequency domain) or OFDM symbolsor allocation units (if applied in time domain) over which to calculatean averaged (or weighted) channel estimate to improve channelestimation.

A filter normalization may be used to facilitate correct scaling of thefiltered channel estimates, e.g. for the case when the filter span orrange covers resource elements not containing channel estimates (or notcarrying reference signaling symbols or signaling measured on).

It may be considered that resource element not containing a channelestimate is outside the frequency or time domain allocation of thechannel for which channel estimation filtering is performed.

In some cases, a resource element not containing a channel estimate maybe within the frequency and time domain allocation of the channel forwhich channel estimation filtering is performed.

In general, a resource element or subcarrier not containing a channelestimate may be considered a subcarrier not carrying signaling based onwhich a channel estimate for the channel may be determined, e.g. notcarrying DMRS or control signaling or data signaling or other referencesignaling; for example, no DMRS modulation symbol may be associated tothe subcarrier, in particular in a case in which DMRS is transmitted ina comb. However, based on approaches described herein, a channelestimate value may be associated to this RE or SC, based on processingother subcarriers, e.g. in the same subset of subcarriers and/orneighbouring or in the range. It may be considered that a RE or SC notcontaining a channel estimate refers to the signaling suitable orintended for performing channel estimation for the subcarrier or UE: achannel estimate value being associated to a SC or RE may refer to theresult of the channel estimation over multiple SCs or REs or PRBs.

A resource element or SC not containing a channel estimate may be aresource element or not SC not containing a DMRS symbol.

It may be considered that normalization may be based on filtercoefficients and/or an impulse train with impulses corresponding toresource element or SC positions containing a channel estimate.

The channel estimation may pertain to estimating the channel for NRPUCCH, and/or the channel estimation may be used on a PUCCHtransmission, and/or for a PUCCH transmission.

It may be considered that the filter length in the time domain may bebased on the duration of the PUCCH format and/or whether or notfrequency hopping is enabled

For example, it may pertain to estimating the channel for NR PUCCHformat 2 and/or NR PUCCH format 3.

In general, channel estimation may pertain to estimating the channel forany OFDM based transmission or SC-FDM based transmission that uses aknown sequence (e.g., signaling sequence or modulation symbol sequence)for channel estimation.

The receiving radio node may comprise radio circuitry, in particularreceiver circuitry or circuitries, and/or transmitter or transceivercircuitry or circuitries, for receiving first (or received) signalingand/or transmitting second signaling (e.g., based on the received/firstsignaling) and/or processing circuitry for processing such, e.g. forperforming a channel estimation. Radio circuitry and/or processingcircuitry may be adapted for receiving and/or determining or performinga channel estimation.

Receiving may comprise demodulating and/or decoding the first signaling,in particular data signaling and/or communication signaling and/orcontrol signaling associated thereto and/or comprised therein, e.g.based on the channel estimation. Processing signaling may comprisedemodulating, and/or decoding, and/or channel estimation, and/orperforming an ICI correction, and/or filtering of or for signaling. Thereceiving radio node may be implemented as a wireless device or terminalor UE or feedback radio node; however, in some variants it may beimplemented as network node or signaling radio node.

The transmitting radio node may comprise radio circuitry, in particulartransmitter circuitry or circuitries and/or receiver and/or transceivercircuitry or circuitries, for transmitting the first signaling and/orreceiving second signaling, and/or may comprise processing circuitry forprocessing such. Radio circuitry and/or processing circuitry may beadapted for modulating and/or coding the first signaling and/or thedemodulating and/or decoding the second signaling, in particular datasignaling and/or communication signaling and/or control signalingassociated thereto and/or comprised therein, and/or mapping referencesignaling symbols and/or data or control signaling associated thereto tofrequency resources. The transmitting radio node may be implemented as anetwork node or base station or signaling radio node; however, in somevariants it may be implemented as wireless device or terminal or UE orfeedback radio node. In general, the transmitting radio node may beadapted for, and/or perform, configuring the receiving radio node, e.g.for receiving the signaling and/or transmitting second signaling and/orperforming the channel estimation, e.g. in particular regarding one ormore parameters, like number of SC in a subset and/or range (e.g.,NRANGE), or which function to use for channel estimation. Suchconfiguring may be higher layer signaling, e.g. RRC layer signaling orRLC layer signaling. The transmitting radio node may be implemented as anetwork node or base station or signaling radio node; however, in somevariants it may be implemented as wireless device or terminal or UE orfeedback radio node.

Processing of or for signaling may comprise modulating, and/or coding,and/or mapping the signaling and/or symbols thereof, e.g. fortransmitting. Alternatively, processing of signaling may compriseperforming a channel estimation and/or demodulation and/or decoding,e.g. based on channel estimation. Processing may comprise determining ameasurement report based on a channel estimation, e.g. for transmittingthe measurement report.

Signaling like first signaling and second signaling may each comprisedata signaling and/or control signaling and/or communication signalingand/or may represent reference signaling. Reference signaling may beassociated to signaling, e.g. DMRS and/or PTRS; in some cases, referencesignaling may be CSI-RS. First PTRS and/or DMRS may be associated to thedata signaling and/or control signaling and/or communication signalingof the first signaling. Second PTRS and/or DMRS may be associated to thedata signaling and/or control signaling and/or communication signalingof the second signaling.

In general, the wireless device and/or network node may operate in,and/or the communication and/or signaling may be in, TDD operation. Itshould be noted that the transmission of signaling from transmissionsources may be synchronised and simultaneous; a shift in time may occurdue to different propagation times, e.g. due to different beams and/orsource locations.

Reference signaling like PTRS (Phase Tracking RS) or DMRS may beconsidered associated to a data block or control signaling or datasignaling or communication signaling if it allows and/or is intended toallow demodulation and/or correction for phase noise or phase errors ofthe signaling associated to the data block and/or the information orsignaling, e.g. based on processing and/or filtering based on receivedreference signaling.

A wireless device and/or feedback radio node (a wireless device may beconsidered an example for a feedback radio node), may in generalcomprise, and/or be adapted to utilise, processing circuitry and/orradio circuitry, in particular a transmitter and/or transceiver and/oreceiver, to process (e.g., trigger and/or schedule) and/or transmitand/or receive signaling like data signaling and/or control signalingand/or reference signaling, in particular first signaling and secondsignaling. A wireless device or feedback radio node may be implementedas terminal or UE; in some cases, it may however be implemented asnetwork node, in particular a base station or relay node or IAB node, inparticular to provide MT (Mobile Termination) functionality for such. Ingeneral, a wireless device of feedback radio node may comprise and/or beadapted for transmission diversity, and/or may be connected orconnectable to, and/or comprise, antenna circuitry, and/or two or moreindependently operable or controllable antenna arrays or arrangements,and/or transmitter circuitries and/or antenna circuitries, and/or may beadapted to use (e.g., simultaneously) a plurality of antenna ports(e.g., for transmitting first signaling and second signaling), e.g.controlling transmission using the antenna array/s, and/or to utiliseand/or operate and/or control two or more transmission sources, to whichit may be connected or connectable, or which it may comprise. Thetransmitting radio node may comprise multiple components and/ortransmitters and/or transmission sources and/or TRPs (and/or beconnected or connectable thereto) and/or be adapted to controltransmission from such. Any combination of units and/or devices able tocontrol transmission on an air interface and/or in radio as describedherein may be considered a transmitting radio node.

A signaling radio node and/or network node (a network node may beconsidered an example of a signaling radio node) may comprise, and/or beadapted to utilise, processing circuitry and/or radio circuitry, inparticular a receiver and/or transmitter and/or transceiver, to transmitand/or to process and/or receive (e.g. receive and/or demodulate and/ordecode and/or perform blind detection and/or schedule or trigger) datasignaling and/or control signaling and/or reference signaling, inparticular first signaling and second signaling. Receiving may comprisescanning a frequency range (e.g., a carrier) for reference signalingand/or control signaling, e.g. at specific (e.g., predefined and/orconfigured) locations in time/frequency domain, which may be dependenton the carrier and/or system bandwidth. Such location/s may correspondto one or more location or resource allocations configured or indicatedor scheduled or allocated to a feedback radio node, e.g. scheduleddynamically, or configured, e.g. with DCI and/or RRC signaling, e.g. fortransmission on resources allocated for data signaling. In some cases, asignaling radio node may be a network node or base station or TRP, ormay be an IAB node or relay node, e.g. providing control levelfunctionality for such, e.g. DU and/or CU functionality. In some cases,e.g. sidelink scenarios, a signaling radio node may be implemented as awireless device or terminal or UE. A signaling radio node or networknode may comprise one or more independently operable or controllablereceiving circuitries and/or antenna circuitries and/or may be adaptedto utilise and/or operate to receive from one or more transmissionsource simultaneously and/or separately (in time domain), and/or tooperate using (e.g., receiving) two or more antenna portssimultaneously, and/or may be connected and/or connectable and/orcomprise multiple independently operable or controllable antennas orantenna arrays or subarrays.

An allocation unit may be considered to be associated to referencesignaling or a reference signaling sequence if it carries at least acomponent of the reference signaling (e.g., a component of referencesignaling is transmitted on the allocation unit). An allocation unit mayin particular represent a time interval, e.g. a block symbol or theduration of a SC-FDM symbol, or OFDM symbol or equivalent, and/or may bebased on the numerology used for the synchronisation signaling, and/ormay represent a predefined time interval. The duration (in time domain)of an allocation unit may be associated to a bandwidth in frequencydomain, e.g. a subcarrier spacing or equivalent, e.g. a minimum usablebandwidth and/or a bandwidth of an allocation unit. It may be consideredthat signaling spanning an allocation unit corresponds to the allocationunit (time interval) carrying the signaling and/or signaling beingtransmitted (or received) in the allocation unit. Transmission ofsignaling and reception of signaling may be related in time by a pathtravel delay the signaling requires to travel from the transmitter toreceiver (it may be assumed that the general arrangement in time isconstant, with path delay/multi path effects having limited effect onthe general arrangement of signaling in time domain). Allocation unitsassociated to different signalings, e.g. different reference signalings,in particular on different ports or TPs. may be considered to beassociated to each other and/or correspond to each other if theycorrespond to the same number of allocation unit within a referencesignaling transmission time interval, and/or if they are synchronised toeach other and/or are simultaneous, e.g. in two simultaneoustransmissions. Similar reasoning may pertain to a transmission timeinterval; the same interval for two signalings may be the intervalshaving the same number and/or relative location in the frame or timingstructure associated to each signaling.

A reference signaling sequence (or shorter, signaling sequence) maycorrespond to a sequence of modulation symbols (e.g., in time domain,after DFT-spreading for a SC-FDM system, or in frequency domain for anOFDM system). The signaling sequence may be predefined. The set ofmodulation symbols used for the signaling sequence may be different fromthe set of modulation symbols used for communication signaling; inparticular, the reference signaling and/or signaling sequence mayrepresent different constellations in modulation and/or phase space thanthe communication signaling.

There is also described a program product comprising instructionscausing processing circuitry to control and/or perform a method asdescribed herein.

Moreover, a carrier medium arrangement carrying and/or storing a programproduct as described herein is considered. An information systemcomprising, and/or connected or connectable, to a radio node is alsodisclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are provided to illustrate concepts and approachesdescribed herein, and are not intended to limit their scope. Thedrawings comprise:

FIG. 1, showing an exemplary channel estimation scenario;

FIG. 2, showing another exemplary channel estimation scenario;

FIG. 3, showing an exemplary (e.g., receiving) radio node; and

FIG. 4, showing another exemplary (e.g., transmitting) radio node.

DETAILED DESCRIPTION

In the following, concepts are explained with reference to NR. However,the concepts and approaches may be applicable to other systems andtechnology.

Channel estimation for PUCCH in NR is traditionally done per physicalresource block (PRB) or per multiple PRBs. First, the channel for eachsubcarrier is estimated. The noise in the channel estimate is reduced bycalculating the average channel within each PRB, or over multiple PRBs,using the estimated channels for each individual subcarrier. While thiswork well for lower subcarrier spacings (SCSs), 15 kHz up to about 120kHz depending also on for example the delay spread of the channel, itdoes not work well for higher SCSs. The reason is that for the higherSCSs the channels for the different subcarriers within the PRB are toodifferent, due to the higher dispersion of the channel, for the averagedchannel to become representative for the whole PRB.

Averaging all subcarriers within a PRB into one channel estimate per PRBis good for reducing noise in the channel estimate but it is not goodfor tracking differences of the channel between the differentsubcarriers. A proposed solution is to average over a subset ofsubcarriers within a PRB to minimize the impact of the varying channelbut keeping some of the noise suppression from the averaging. Thisresults in multiple resulting channel estimates per PRB, mapping todifferent sets of subcarriers within the PRB. The number of subcarriersto use in each set is a trade-off between noise suppression and theability to handle channel variations.

The invention improves the channel estimation performance in highersubcarrier spacings, for example 480 kHz and 960 kHz.

In a traditional method of averaging over a PRB, the resulting channelestimate is used for all subcarriers within that same PRB. ĥ_(k) is thechannel estimated for subcarrier k. The resulting channel estimate forPRB n is ĥ¹², applied in operation for all subcarriers of the PRB. Thisis assuming that all subcarriers within the PRB are used for DMRS,otherwise non-DMRS subcarriers are removed from the sum and thenormalization is reduced accordingly.

One solution to improve the channel estimates is to average over asubset of subcarriers to minimize the impact of the varying channel butkeeping some of the noise suppression from the averaging. This resultsin multiple resulting channel estimates per PRB, mapping to differentsets of subcarriers within the PRB. The number of subcarriers to use ineach set may be based on analysing a trade-off between noise suppressionand the ability to handle channel variations.

In FIG. 1, averaging over a subset of subcarriers within a PRB, in thiscase 6 subcarriers per subset is shown. The resulting channel estimatesare used for all subcarriers within those same subsets. ĥ_(k) is thechannel estimated for subcarrier k. The resulting channel estimates forPRB n are ĥ_(A) ⁶ and ĥ_(B) ⁶. This is assuming that all subcarrierswithin the PRB are used for DMRS, otherwise non-DMRS subcarriers areremoved from the sums and the normalizations are reduced accordingly.

In FIG. 2, averaging over a subset of subcarriers within a PRB is shown,in this case 3 subcarriers per subset. The resulting channel estimatesare used for all subcarriers within those same subsets. ĥ_(k) is thechannel estimated for subcarrier k. The resulting channel estimates forPRB n are ĥ_(A) ³, ĥ_(B) ³, ĥ_(C) ³ and ĥ_(D) ³. This is assuming thatall subcarriers within the PRB are used for DMRS, otherwise non-DMRSsubcarriers may be removed from the sums and the normalizations arereduced accordingly.

Another solution is to improve the channel estimates using a filteringoperation. Denote the initial channel estimate for subcarrier n withĥ(n), n=0, . . . , N−1, where N=N_(PRB) ^(sc)·N_(PRB). For the purposeof zero-padding, let ĥ(n)=0, n≠0, . . . , N−1. N_(PRB)=12 is the numberof subcarriers per PRB and N_(PRB) is the number of allocated PRBs. Ifthe DMRS does not cover all subcarriers the initial channel estimatesfor the subcarriers not covered by the DMRS are set to 0. The improvedchannel estimate for subcarrier n is

${{{\overset{\hat{}}{h}}_{f}(n)} = {\frac{1}{G(n)}{\sum\limits_{k = {- L_{e}}}^{L_{s}}{{g(k)}{\overset{\hat{}}{h}( {n - k} )}}}}},{n = 0},\ldots,{N - 1}$

where g(k), k=−L_(e), . . . , L_(s) is an appropriate filter,L=L_(e)+L_(s)+1 is the filter length and G(n) is a filter normalization.The purpose of the filter normalization G(n) is to adjust thenormalization if the initial channel estimate for a particularsubcarrier is 0, e.g. a non-DMRS subcarrier or zero-padding for thefilter. The filter normalization is

${{G(n)} = {\sum\limits_{k = {- L_{e}}}^{L_{s}}{{g(k)}{b( {n - k} )}}}},{n = 0},\ldots,{N - 1}$

where

${b(n)} = \{ {\begin{matrix}{1,} & {{\hat{h}(n)} \neq 0} \\{0,} & {{\hat{h}(n)} = 0}\end{matrix}{\forall n}} $

For each n, G(n) is the sum of all filter coefficients that in thefiltering operation are multiplied by a non-zero input from ĥ(n). Asdescribed above G(n) depends on the input data ĥ(n). Note: “input data”in this context means the channel estimates that are the input to thefilter g(k). G(n) makes sure that the scale of the output ĥ_(f)(n) iscorrect and not affected by zeros in the input data ĥ(n). Zeros in theinput data occur in the edge cases, i.e. zero padding before and afterthe data, but can also occur inside the data if one or multiplesubcarriers does not have any DMRS symbol.

If the number of adjacent non-DMRS subcarriers are larger than thefilter length L the filter normalization G(n) will become 0 for some n,this should be handled to avoid division by 0. G(n) for those n can beset to 1 since the filter output for those same n are anyway 0.

For non-DMRS subcarriers, the filter g(k) may act as an interpolationfilter using initial channel estimates from nearby subcarriers toproduce a channel estimate also for the non-DMRS subcarriers. Theproperties of this interpolation may depend on the choice of filter andfilter length.

The filter can be selected in many ways. For example, it may beconsidered selecting a symmetrical filter that puts less weight on aninitial channel estimate the further away it is, e.g. in a monotonouslyor strictly monotonously (e.g., falling or decreasing) manner ordistribution (e.g., as a weight distribution or filter function). Asymmetrical filter may be referred to as L_(e)=L_(s). For example, asymmetrical filter may be a triangular filter or a bell-shaped filter ora gaussian-filter. Alternatively, a brick wall filter may be considered,which may perform a moving average of the initial channel estimates thatfall within the span of the filter.

The filter length, L, should be selected such that when calculating thechannel for a subcarrier very little or no weight are put on thesubcarriers that do not have similar channels. One way to do this is tocalculate the filter length using the subcarrier spacing and the delayspread of the channel. The coherence bandwidth is B≈1/D, where D is thedelay spread. The filter length may be calculated as

$L = \lfloor \frac{\alpha B}{S} \rfloor$

where S is the subcarrier spacing, α is a scaling factor and └⋅┘ is thefloor operator. If a symmetric filter is desired, L should be selectedto be odd. That can be done according to the following update function.

L←{L−(1−mod(L,2))}

where mod(⋅,2) is the modulo-2 operator.

The solutions have been evaluated by means of simulation. For thefilter-solution the length of the filter is calculated using α=0.2 andthe filter is a symmetrical triangular filter with L_(e)=L_(s) definedaccording to

${{g(k)} = {\lceil \frac{L}{2} \rceil - {❘k❘}}},{k = {- \lfloor \frac{L}{2} \rfloor}},\ldots,\lfloor \frac{L}{2} \rfloor$

where ┌⋅┐ is the ceil operator, └⋅┘ is the floor operator and |⋅| is theabsolute value operator.

The performance for the filtering solution (with triangular filter) andthe block averaging solution over subsets with the size of 3 and 6subcarriers compared to averaging over 12 subcarriers have beenevaluated. Performance depends a lot on how many subcarriers that areused for averaging. For the averaging solution, 6 subcarriers mayperform best for 480 kHz and averaging over 3 subcarriers best for 960kHz. The reason for this is that the channel varies more between thesubcarriers for 960 kHz than for 480 kHz. The filtering solution with anadaptive filter length is best in all cases, outperforming all othersolutions for 480 kHz and 960 kHz while giving the same performance asthe traditional 12 subcarriers averaging for 120 kHz. The filter lengthsused in the evaluation are calculated according to the formulas aboveusing a delay spread of 40 ns and as already mentioned α=0.2. The filterlengths used are L=41 for 120 kHz SCS, L=9 for 480 kHz SCS and L=5 for960 kHz SCS.

The filtering solution described above is described for filtering in thefrequency domain. The same filtering approach can be applied in the timedomain, e.g. across OFDM symbols or allocation units. In the frequencydomain, the spacing between subcarriers increase with an increasingsubcarrier spacing. In the time domain, the spacing between OFDM symbolsor allocation units decrease, the symbols become shorter, withincreasing subcarrier spacing. Because of this, the formula forcalculating the filter length for application in time domain may betransformed to

$L_{TD} = \lfloor \frac{\beta S}{f_{D}} \rfloor$

f_(D) is the Doppler spread of the channel and β is a scaling factor.For the time domain filtering, L_(TD) is used in place of L in allformulas described above. For cases with high subcarrier spacing, thesymbol duration becomes very short. With a very short symbol duration,the channel may not show much variation between the symbols. In thosecases, estimating the channel with averaging of the initial channelestimates over multiple symbols or allocation units may be sufficient toprovide reliable channel estimation.

FIG. 3 schematically shows a radio node, in particular a wireless deviceor terminal 10 or a UE (User Equipment). Radio node 10 comprisesprocessing circuitry (which may also be referred to as controlcircuitry) 20, which may comprise a controller connected to a memory.Any module of the radio node 10, e.g. a communicating module ordetermining module, may be implemented in and/or executable by, theprocessing circuitry 20, in particular as module in the controller.Radio node 10 also comprises radio circuitry 22 providing receiving andtransmitting or transceiving functionality (e.g., one or moretransmitters and/or receivers and/or transceivers), the radio circuitry22 being connected or connectable to the processing circuitry. Anantenna circuitry 24 of the radio node 10 is connected or connectable tothe radio circuitry 22 to collect or send and/or amplify signals. Radiocircuitry 22 and the processing circuitry 20 controlling it areconfigured for cellular communication with a network, e.g. a RAN asdescribed herein, and/or for sidelink communication (which may be withincoverage of the cellular network, or out of coverage; and/or may beconsidered non-cellular communication and/or be associated to anon-cellular wireless communication network). Radio node 10 maygenerally be adapted to carry out any of the methods of operating aradio node like terminal or UE disclosed herein; in particular, it maycomprise corresponding circuitry, e.g. processing circuitry, and/ormodules, e.g. software modules. It may be considered that the radio node10 comprises, and/or is connected or connectable, to a power supply.

FIG. 4 schematically shows a radio node 100, which may in particular beimplemented as a network node 100, for example an eNB or gNB or similarfor NR. Radio node 100 comprises processing circuitry (which may also bereferred to as control circuitry) 120, which may comprise a controllerconnected to a memory. Any module, e.g. transmitting module and/orreceiving module and/or configuring module of the node 100 may beimplemented in and/or executable by the processing circuitry 120. Theprocessing circuitry 120 is connected to control radio circuitry 122 ofthe node 100, which provides receiver and transmitter and/or transceiverfunctionality (e.g., comprising one or more transmitters and/orreceivers and/or transceivers). An antenna circuitry 124 may beconnected or connectable to radio circuitry 122 for signal reception ortransmittance and/or amplification. Node 100 may be adapted to carry outany of the methods for operating a radio node or network node disclosedherein; in particular, it may comprise corresponding circuitry, e.g.processing circuitry, and/or modules. The antenna circuitry 124 may beconnected to and/or comprise an antenna array. The node 100,respectively its circuitry, may be adapted to perform any of the methodsof operating a network node or a radio node as described herein; inparticular, it may comprise corresponding circuitry, e.g. processingcircuitry, and/or modules. The radio node 100 may generally comprisecommunication circuitry, e.g. for communication with another networknode, like a radio node, and/or with a core network and/or an internetor local net, in particular with an information system, which mayprovide information and/or data to be transmitted to a user equipment.

Aspects regarding QCL may be considered. For example, several signalsmay be transmitted from different antenna ports and/or transmissionsources associated to the same base station at a same or different time.If these signals have the same large-scale properties such as Dopplershift/spread, average delay spread, or average delay, these antennaports are said to be quasi co-located (QCL) with respect to thelarge-scale properties. If a UE knows that two antenna ports are QCLwith respect to a certain parameter (e.g. Doppler spread), the UE canestimate that parameter based on a first antenna port and apply thatestimate for receiving signal on the second antenna port. Typically, ameasurement reference signal (RS) such as NZP CSI-RS (Non-Zero PowerChannel State Information Reference Signal) or SSB (SynchronizationSignal Block), known as source RS, is sent on the first antenna andanother signal such as a demodulation reference signal (DMRS), known astarget RS, is sent on the second antenna port. For instance, if antennaports A and B are QCL with respect to average delay, the UE can estimatethe average delay from the signal received from antenna port A andassume that the signal received from antenna port B has the same averagedelay. This is useful for demodulation because in some scenarios,certain channel properties cannot be reliably estimated based on signals(e.g., DMRS) received on port B. With the QCL relation, the UE can firstmeasure certain channel properties on antenna port A and apply anappropriate channel estimation filter when receiving signals on antennaport B. Information about what assumptions can be made regarding QCL issignaled to the UE from the network. In NR, four types of QCL relationsbetween a transmitted source RS and transmitted target RS were defined:

Type A: {Doppler shift, Doppler spread, average delay, delay spread}Type B: {Doppler shift, Doppler spread}Type C: {average delay, Doppler shift}Type D: {Spatial Rx parameter}QCL type D is known as spatial QCL. There is currently no strictdefinition of spatial QCL, but the understanding is that if twotransmitted antenna ports are spatially QCL, the UE can use the same Rxbeam to receive them.

TCI states may be considered. A QCL relation between two RS may besignaled or indicated to a UE or wireless device through so called TCI(Transmission Configuration Indicator) states. Each TCI state cancontain one or two source RS and associated QCL type. For example, a TCIstate may contain a pair of source RS and QCL types, e.g., {NZP CSI-RS1,QCL Type A} and {NZP CSI-RS2, QCL Type D}. In this example, the UE canderive Doppler shift, Doppler spread, average delay, delay spread fromNZP CSI-RS1 and Spatial Rx parameter (i.e. the RX beam to use) from NZPCSI-RS2. A TCI state can be interpreted as a possible beam transmittedfrom the network and/or a possible TRP (Transmission Point) used by thenetwork to communicate with the UE. A UE may be configurable through RRCsignaling, e.g. with up to 8 TCI states in FR1 and 128 TCI states in FR2for PDSCH, depending on UE capability. Up to 8 TCI states per BWP(Bandwidth Part) per serving cell may be activated by MAC (Medium AccessControl) CE (Control Element). The UE determines QCL for a PDSCHreception based on the TCI-State(s) indicated in the ‘TransmissionConfiguration Indication’ field in a DCI scheduling the PDSCH. A mappingbetween a TCI codepoint in DCI and one or two TCI states may be providedin the enhanced PDSCH MAC CE that activates the TCI states.

In some variants, a search space set may be defined over a CORESET. ACORESET may consist of N_(RB) ^(CORESET) resource blocks in thefrequency domain and N_(symb) ^(CORESET)∈{1,2,3} consecutive OFDMsymbols in the time domain. For each DL BWP configured to a UE in aserving cell, a UE may be provided by higher layer signalling with P≤5CORESETs. For each CORESET, a UE may be configured by RRC (RadioResource Control) signaling with CORESET information element (IE), whichmay include one or more of:

-   -   ControlResourceSetId: a CORESET index p, 0≤p<16;    -   a DM-RS scrambling sequence initialization value;    -   a list of up to 64 TCI-States can be configured in a CORESET p;    -   an indication for a presence or absence of a transmission        configuration indication (TCI) field for DCI format 1_1        transmitted by a PDCCH in CORESET p. The corresponding field for        indicating a presence or absence of a TCI field for DCI format        1_2 is given by ‘tci-PresentInDCI-ForDCIFormat1_2’.

In general, for each CORESET or control region, one TCI state may beactivated and/or associated, e.g. by a MAC CE transmitted by a networknode.

Single-DCI based DL data transmission over Multiple Transmission Points(TRP) may be considered. A PDSCH, which in general may correspond todata signaling, and/or a data block (in particular, a transport block orcode block bundle) may be transmitted to a UE from multiple TRPs. Sincedifferent TRPs may be located in different physical locations and/orhave different beams, the propagation channels can be different. Tofacilitate receiving PDSCH data from different TRPs or beams, a UE maybe indicated with two TCI states, each associated with a TRP or a beam,by a single codepoint of a TCI field in a DCI. The network may configurethe UE with multiple TCI states via RRC. Whether a codepoint in the TCIfield is mapped to one or two TCI states may be provided by an enhancedPDSCH MAC CE that activates the TCI states.

As one example of PDSCH transmission over two TRPs, a case may beconsidered in which different layers of a PDSCH are sent over two TRPs,each associated with a different TCI state. In this case, two DMRSports, one for each layer, in two CDM (Code Division Multiplex, shiftedby different codes) groups may also be signaled to the UE. A first TCIstate is associated with the DMRS port in a first CDM group, and asecond TCI state is associated with the DMRS port in a second CDM group.This approach may be referred to as NC-JT (Non-coherent jointtransmission) or scheme In this context, a single CW (codeword, e.g.associated to one data block) may be transmitted over two TRPs.

Transmitting PDSCH over multiple TRPs can also be used to improve PDSCHtransmission reliability. For example, a PDSCH may be sent over TRP1 inPRGs (precoding RB group) {0,2,4} and over TRP2 in PRGs {1,3,5}. ThePDSCH is scheduled by a PDCCH or DCI which may be sent over TRP1, i.e.associated with TCI state 1. In another variant, PDSCH Occasion #1 maybe transmitted in PRGs {0,2,4} from TRP1 and PDSCH Occasion #2 with thesame TB may be transmitted in PRGs {1,3,5} from TRP2. The two PDSCHOccasions may carry the same encoded data payload, and may have thesame, or different redundancy version; the UE or wireless device mayperform soft combining of the two PDSCHs to achieve more reliablereception.

In some cases, data transmission with PDSCH repetition may be utilised,e.g. such that repetition of one PDSCH (e.g., codeword and/or datablock) may occurs within a slot, with different transmission sources orTRP (e.g., with different QCL or TCI) transmitting different occasionsof the repetitions. For example, each transmission may be in a mini slotof 4 OFDM symbols within a slot; transmission in different mini-slotsmay be provided by different transmission sources or TRPs. Each PDSCHtransmission may be associated with a same or different RV. For theseschemes, a single DCI transmitted from one TRP may be used to schedulemultiple PDSCH transmissions over two TRPs.

Alternatively, Multi-DCI based PDSCH transmission with multiple TRPs maybe considered. Multi-DCI scheduling for multi-TRP may refer to cases inwhich a UE or WD may receive two or more DCIs, each DCI scheduling aPDSCH. Each PDCCH and the corresponding (scheduled) PDSCH may betransmitted from the same TRP. For example, a PDSCH1 may be scheduled byPDCCH 1 from TRP1, and PDSCH2 may be scheduled by PDCCH 2 from TRP2. Thetwo PDSCHs may be fully, partially, or non-overlapping in time and/orfrequency. When the two PDSCHs are fully or partially overlapping, asame DMRS resource configuration may be assumed with DMRS ports of thetwo PDSCHs in different CDM groups and/or shifted relative to each otheraccording to another approach. For multi-DCI operation, a UE may beconfigured with two CORESET pools, each associated with a TRP. EachCORESET pool may correspond to a collection of CORESETs that belongs tothe same pool. A CORESET pool index can be configured in each CORESET,e.g. with a value of 0 or 1. For the two Das in the above example, theymay be transmitted in two CORESETs belonging to different CORESET pools(i.e. with CORESETPoolIndex 0 and 1 respectively). The two PDSCHs may beassociated to, and/or belong to, two different HARQ processes. Formulti-DCI based PDSCH scheduling, TCI state activation and mapping tocodepoints of the TCI field in DCI may be per CORESET pool; only asingle TCI state may be mapped to a codepoint of TCI field in DCI. Thismeans that a DCI sent in a CORESET pool can only schedule a PDSCH fromone TRP.

In general, a block symbol and/or an allocation unit may representand/or correspond to an extension in time domain, e.g. a time interval.A block symbol duration (the length of the time interval) may correspondto the duration of an OFDM symbol or a corresponding duration, and/ormay be based and/or defined by a subcarrier spacing used (e.g., based onthe numerology) or equivalent, and/or may correspond to the duration ofa modulation symbol (e.g., for OFDM or similar frequency domainmultiplexed types of signaling). It may be considered that a blocksymbol comprises a plurality of modulation symbols, e.g. based on asubcarrier spacing and/or numerology or equivalent, in particular fortime domain multiplexed types (on the symbol level for a singletransmitter) of signaling like single-carrier based signaling, e.g.SC-FDE or SC-FDMA (in particular, FDF-SC-FDMA or pulse-shaped SC-FDMA).The number of symbols may be based on and/or defined by the number ofsubcarrier to be DFTS-spread (for SC-FDMA) and/or be based on a numberof FFT samples, e.g. for spreading and/or mapping, and/or equivalent,and/or may be predefined and/or configured or configurable. A blocksymbol in this context may comprise and/or contain a plurality ofindividual modulation symbols, which may be for example 1000 or more, or3000 or more, or 3300 or more. The number of modulation symbols in ablock symbol may be based and/or be dependent on a bandwidth scheduledfor transmission of signaling in the block symbol. A block symbol and/ora number of block symbols (an integer smaller than 20, e.g. equal to orsmaller than 14 or 7 or 4 or 2 or a flexible number) may be a unit(e.g., allocation unit) used or usable or intended e.g. for schedulingand/or allocation of resources, in particular in time domain. To a blocksymbol (e.g., scheduled or allocated) and/or block symbol group and/orallocation unit, there may be associated a frequency range and/orfrequency domain allocation and/or bandwidth allocated for transmission.

An allocation unit, and/or a block symbol, may be associated to aspecific (e.g., physical) channel and/or specific type of signaling, forexample reference signaling. In some cases, there may be a block symbolassociated to a channel that also is associated to a form of referencesignaling and/or pilot signaling and/or tracking signaling associated tothe channel, for example for timing purposes and/or decoding purposes(such signaling may comprise a low number of modulation symbols and/orresource elements of a block symbol, e.g. less than 10% or less than 5%or less than 1% of the modulation symbols and/or resource elements in ablock symbol). To a block symbol, there may be associated resourceelements; a resource element may be represented in time/frequencydomain, e.g. by the smallest frequency unit carrying or mapped to (e.g.,a subcarrier) in frequency domain and the duration of a modulationsymbol in time domain. A block symbol may comprise, and/or to a blocksymbol may be associated, a structure allowing and/or comprising anumber of modulation symbols, and/or association to one or more channels(and/or the structure may dependent on the channel the block symbol isassociated to and/or is allocated or used for), and/or referencesignaling (e.g., as discussed above), and/or one or more guard periodsand/or transient periods, and/or one or more affixes (e.g., a prefixand/or suffix and/or one or more infixes (entered inside the blocksymbol)), in particular a cyclic prefix and/or suffix and/or infix. Acyclic affix may represent a repetition of signaling and/or modulationsymbol/s used in the block symbol, with possible slight amendments tothe signaling structure of the affix to provide a smooth and/orcontinuous and/or differentiable connection between affix signaling andsignaling of modulation symbols associated to the content of the blocksymbol (e.g., channel and/or reference signaling structure). In somecases, in particular some OFDM-based waveforms, an affix may be includedinto a modulation symbol. In other cases, e.g. some single carrier-basedwaveforms, an affix may be represented by a sequence of modulationsymbols within the block symbol. It may be considered that in some casesa block symbol is defined and/or used in the context of the associatedstructure.

In some variants, a reference beam and/or reference beams and/orreference signaling may correspond to and/or carry random accesssignaling, e.g. a random access preamble. Such a reference beam orsignaling may be transmitted by another radio node. The signaling mayindicate which beam is used for transmitting. Alternatively, thereference beams may be beams receiving the random access signaling.Random access signaling may be used for initial connection to the radionode and/or a cell provided by the radio node, and/or for reconnection.Utilising random access signaling facilitates quick and early beamselection. The random access signaling may be on a random accesschannel, e.g. based on broadcast information provided by the radio node(the radio node performing the beam selection), e.g. withsynchronisation signaling (e.g., SSB block and/or associated thereto).The reference signaling may correspond to synchronisation signaling,e.g. transmitted by the radio node in a plurality of beams. Thecharacteristics may be reported on by a node receiving thesynchronisation signaling, e.g. in a random access process, e.g. a msg3for contention resolution, which may be transmitted on a physical uplinkshared channel based on a resource allocation provided by the radionode.

Data signaling may be on a data channel, for example on a PDSCH orPSSCH, or on a dedicated data channel, e.g. for low latency and/or highreliability, e.g. a URLLC channel. Control signaling may be on a controlchannel, for example on a common control channel or a PDCCH or PSCCH,and/or comprise one or more DCI messages or SCI messages. Referencesignaling may be associated to control signaling and/or data signaling,e.g. DM-RS and/or PT-RS.

Reference signaling, for example, may comprise DM-RS and/or pilotsignaling and/or discovery signaling and/or synchronisation signalingand/or sounding signaling and/or phase tracking reference signalingand/or cell-specific reference signaling and/or user-specific signaling,in particular CSI-RS. Reference signaling or signaling in general may besignaling with one or more signaling characteristics, in particulartransmission power and/or sequence of modulation symbols and/or resourcedistribution and/or phase distribution known to the receiver. Thus, thereceiver can use the reference signaling as a reference and/or fortraining and/or for compensation. The receiver can be informed about thereference signaling by the transmitter, e.g. being configured and/orsignaling with control signaling, in particular physical layer signalingand/or higher layer signaling (e.g., DCI and/or RRC signaling), and/ormay determine the corresponding information itself, e.g. a network nodeconfiguring a UE to transmit reference signaling. Reference signalingmay be signaling comprising one or more reference symbols and/orstructures. Reference signaling may be adapted for gauging and/orestimating and/or representing transmission conditions, e.g. channelconditions and/or transmission path conditions and/or channel (or signalor transmission) quality. It may be considered that the transmissioncharacteristics (e.g., signal strength and/or form and/or modulationand/or timing) of reference signaling are available for both transmitterand receiver of the signaling (e.g., due to being predefined and/orconfigured or configurable and/or being communicated). Different typesof reference signaling may be considered, e.g. pertaining to uplink,downlink or sidelink, cell-specific (in particular, cell-wide, e.g.,CRS) or device or user specific (addressed to a specific target or userequipment, e.g., CSI-RS), demodulation-related (e.g., DMRS) and/orsignal strength related, e.g. power-related or energy-related oramplitude-related (e.g., SRS or pilot signaling) and/or phase-related,etc.

References to specific resource structures like an allocation unitand/or block symbol and/or block symbol group and/or transmission timingstructure and/or symbol and/or slot and/or mini-slot and/or subcarrierand/or carrier may pertain to a specific numerology, which may bepredefined and/or configured or configurable. A transmission timingstructure may represent a time interval, which may cover one or moresymbols. Some examples of a transmission timing structure aretransmission time interval (TTI), subframe, slot and mini-slot. A slotmay comprise a predetermined, e.g. predefined and/or configured orconfigurable, number of symbols, e.g. 6 or 7, or 12 or 14. A mini-slotmay comprise a number of symbols (which may in particular beconfigurable or configured) smaller than the number of symbols of aslot, in particular 1, 2, 3 or 4, or more symbols, e.g. less symbolsthan symbols in a slot. A transmission timing structure may cover a timeinterval of a specific length, which may be dependent on symbol timelength and/or cyclic prefix used. A transmission timing structure maypertain to, and/or cover, a specific time interval in a time stream,e.g. synchronized for communication. Timing structures used and/orscheduled for transmission, e.g. slot and/or mini-slots, may bescheduled in relation to, and/or synchronized to, a timing structureprovided and/or defined by other transmission timing structures. Suchtransmission timing structures may define a timing grid, e.g., withsymbol time intervals within individual structures representing thesmallest timing units. Such a timing grid may for example be defined byslots or subframes (wherein in some cases, subframes may be consideredspecific variants of slots). A transmission timing structure may have aduration (length in time) determined based on the durations of itssymbols, possibly in addition to cyclic prefix/es used. The symbols of atransmission timing structure may have the same duration, or may in somevariants have different duration. The number of symbols in atransmission timing structure may be predefined and/or configured orconfigurable, and/or be dependent on numerology. The timing of amini-slot may generally be configured or configurable, in particular bythe network and/or a network node. The timing may be configurable tostart and/or end at any symbol of the transmission timing structure, inparticular one or more slots.

There is generally considered a program product comprising instructionsadapted for causing processing and/or control circuitry to carry outand/or control any method described herein, in particular when executedon the processing and/or control circuitry. Also, there is considered acarrier medium arrangement carrying and/or storing a program product asdescribed herein.

A carrier medium arrangement may comprise one or more carrier media.Generally, a carrier medium may be accessible and/or readable and/orreceivable by processing or control circuitry. Storing data and/or aprogram product and/or code may be seen as part of carrying data and/ora program product and/or code. A carrier medium generally may comprise aguiding/transporting medium and/or a storage medium. Aguiding/transporting medium may be adapted to carry and/or carry and/orstore signals, in particular electromagnetic signals and/or electricalsignals and/or magnetic signals and/or optical signals. A carriermedium, in particular a guiding/transporting medium, may be adapted toguide such signals to carry them. A carrier medium, in particular aguiding/transporting medium, may comprise the electromagnetic field,e.g. radio waves or microwaves, and/or optically transmissive material,e.g. glass fiber, and/or cable. A storage medium may comprise at leastone of a memory, which may be volatile or non-volatile, a buffer, acache, an optical disc, magnetic memory, flash memory, etc.

A system comprising one or more radio nodes as described herein, inparticular a network node and a user equipment, is described. The systemmay be a wireless communication system, and/or provide and/or representa radio access network.

Moreover, there may be generally considered a method of operating aninformation system, the method comprising providing information.Alternatively, or additionally, an information system adapted forproviding information may be considered. Providing information maycomprise providing information for, and/or to, a target system, whichmay comprise and/or be implemented as radio access network and/or aradio node, in particular a network node or user equipment or terminal.Providing information may comprise transferring and/or streaming and/orsending and/or passing on the information, and/or offering theinformation for such and/or for download, and/or triggering suchproviding, e.g. by triggering a different system or node to streamand/or transfer and/or send and/or pass on the information. Theinformation system may comprise, and/or be connected or connectable to,a target, for example via one or more intermediate systems, e.g. a corenetwork and/or internet and/or private or local network. Information maybe provided utilising and/or via such intermediate system/s. Providinginformation may be for radio transmission and/or for transmission via anair interface and/or utilising a RAN or radio node as described herein.Connecting the information system to a target, and/or providinginformation, may be based on a target indication, and/or adaptive to atarget indication. A target indication may indicate the target, and/orone or more parameters of transmission pertaining to the target and/orthe paths or connections over which the information is provided to thetarget. Such parameter/s may in particular pertain to the air interfaceand/or radio access network and/or radio node and/or network node.Example parameters may indicate for example type and/or nature of thetarget, and/or transmission capacity (e.g., data rate) and/or latencyand/or reliability and/or cost, respectively one or more estimatesthereof. The target indication may be provided by the target, ordetermined by the information system, e.g. based on information receivedfrom the target and/or historical information, and/or be provided by auser, for example a user operating the target or a device incommunication with the target, e.g. via the RAN and/or air interface.For example, a user may indicate on a user equipment communicating withthe information system that information is to be provided via a RAN,e.g. by selecting from a selection provided by the information system,for example on a user application or user interface, which may be a webinterface. An information system may comprise one or more informationnodes. An information node may generally comprise processing circuitryand/or communication circuitry. In particular, an information systemand/or an information node may be implemented as a computer and/or acomputer arrangement, e.g. a host computer or host computer arrangementand/or server or server arrangement. In some variants, an interactionserver (e.g., web server) of the information system may provide a userinterface, and based on user input may trigger transmitting and/orstreaming information provision to the user (and/or the target) fromanother server, which may be connected or connectable to the interactionserver and/or be part of the information system or be connected orconnectable thereto. The information may be any kind of data, inparticular data intended for a user of for use at a terminal, e.g. videodata and/or audio data and/or location data and/or interactive dataand/or game-related data and/or environmental data and/or technical dataand/or traffic data and/or vehicular data and/or circumstantial dataand/or operational data. The information provided by the informationsystem may be mapped to, and/or mappable to, and/or be intended formapping to, communication or data signaling and/or one or more datachannels as described herein (which may be signaling or channel/s of anair interface and/or used within a RAN and/or for radio transmission).It may be considered that the information is formatted based on thetarget indication and/or target, e.g. regarding data amount and/or datarate and/or data structure and/or timing, which in particular may bepertaining to a mapping to communication or data signaling and/or a datachannel. Mapping information to data signaling and/or data channel/s maybe considered to refer to using the signaling/channel/s to carry thedata, e.g. on higher layers of communication, with thesignaling/channel/s underlying the transmission. A target indicationgenerally may comprise different components, which may have differentsources, and/or which may indicate different characteristics of thetarget and/or communication path/s thereto. A format of information maybe specifically selected, e.g. from a set of different formats, forinformation to be transmitted on an air interface and/or by a RAN asdescribed herein. This may be particularly pertinent since an airinterface may be limited in terms of capacity and/or of predictability,and/or potentially be cost sensitive. The format may be selected to beadapted to the transmission indication, which may in particular indicatethat a RAN or radio node as described herein is in the path (which maybe the indicated and/or planned and/or expected path) of informationbetween the target and the information system. A (communication) path ofinformation may represent the interface/s (e.g., air and/or cableinterfaces) and/or the intermediate system/s (if any), between theinformation system and/or the node providing or transferring theinformation, and the target, over which the information is, or is to be,passed on. A path may be (at least partly) undetermined when a targetindication is provided, and/or the information is provided/transferredby the information system, e.g. if an internet is involved, which maycomprise multiple, dynamically chosen paths. Information and/or a formatused for information may be packet-based, and/or be mapped, and/or bemappable and/or be intended for mapping, to packets. Alternatively, oradditionally, there may be considered a method for operating a targetdevice comprising providing a target indicating to an informationsystem. More alternatively, or additionally, a target device may beconsidered, the target device being adapted for providing a targetindication to an information system.

In another approach, there may be considered a target indication tooladapted for, and/or comprising an indication module for, providing atarget indication to an information system. The target device maygenerally be a target as described above. A target indication tool maycomprise, and/or be implemented as, software and/or application or app,and/or web interface or user interface, and/or may comprise one or moremodules for implementing actions performed and/or controlled by thetool. The tool and/or target device may be adapted for, and/or themethod may comprise, receiving a user input, based on which a targetindicating may be determined and/or provided. Alternatively, oradditionally, the tool and/or target device may be adapted for, and/orthe method may comprise, receiving information and/or communicationsignaling carrying information, and/or operating on, and/or presenting(e.g., on a screen and/or as audio or as other form of indication),information. The information may be based on received information and/orcommunication signaling carrying information. Presenting information maycomprise processing received information, e.g. decoding and/ortransforming, in particular between different formats, and/or forhardware used for presenting. Operating on information may beindependent of or without presenting, and/or proceed or succeedpresenting, and/or may be without user interaction or even userreception, for example for automatic processes, or target deviceswithout (e.g., regular) user interaction like MTC devices, of forautomotive or transport or industrial use. The information orcommunication signaling may be expected and/or received based on thetarget indication. Presenting and/or operating on information maygenerally comprise one or more processing steps, in particular decodingand/or executing and/or interpreting and/or transforming information.Operating on information may generally comprise relaying and/ortransmitting the information, e.g. on an air interface, which mayinclude mapping the information onto signaling (such mapping maygenerally pertain to one or more layers, e.g. one or more layers of anair interface, e.g. RLC (Radio Link Control) layer and/or MAC layerand/or physical layer/s). The information may be imprinted (or mapped)on communication signaling based on the target indication, which maymake it particularly suitable for use in a RAN (e.g., for a targetdevice like a network node or in particular a UE or terminal). The toolmay generally be adapted for use on a target device, like a UE orterminal. Generally, the tool may provide multiple functionalities, e.g.for providing and/or selecting the target indication, and/or presenting,e.g. video and/or audio, and/or operating on and/or storing receivedinformation. Providing a target indication may comprise transmitting ortransferring the indication as signaling, and/or carried on signaling,in a RAN, for example if the target device is a UE, or the tool for aUE. It should be noted that such provided information may be transferredto the information system via one or more additionally communicationinterfaces and/or paths and/or connections. The target indication may bea higher-layer indication and/or the information provided by theinformation system may be higher-layer information, e.g. applicationlayer or user-layer, in particular above radio layers like transportlayer and physical layer. The target indication may be mapped onphysical layer radio signaling, e.g. related to or on the user-plane,and/or the information may be mapped on physical layer radiocommunication signaling, e.g. related to or on the user-plane (inparticular, in reverse communication directions). The describedapproaches allow a target indication to be provided, facilitatinginformation to be provided in a specific format particularly suitableand/or adapted to efficiently use an air interface. A user input may forexample represent a selection from a plurality of possible transmissionmodes or formats, and/or paths, e.g. in terms of data rate and/orpackaging and/or size of information to be provided by the informationsystem.

In general, a numerology and/or subcarrier spacing may indicate thebandwidth (in frequency domain) of a subcarrier of a carrier, and/or thenumber of subcarriers in a carrier and/or the numbering of thesubcarriers in a carrier, and/or the symbol time length. Differentnumerologies may in particular be different in the bandwidth of asubcarrier. In some variants, all the subcarriers in a carrier have thesame bandwidth associated to them. The numerology and/or subcarrierspacing may be different between carriers in particular regarding thesubcarrier bandwidth. A symbol time length, and/or a time length of atiming structure pertaining to a carrier may be dependent on the carrierfrequency, and/or the subcarrier spacing and/or the numerology. Inparticular, different numerologies may have different symbol timelengths, even on the same carrier.

Signaling may generally comprise one or more (e.g., modulation) symbolsand/or signals and/or messages. A signal may comprise or represent oneor more bits. An indication may represent signaling, and/or beimplemented as a signal, or as a plurality of signals. One or moresignals may be included in and/or represented by a message. Signaling,in particular control signaling, may comprise a plurality of signalsand/or messages, which may be transmitted on different carriers and/orbe associated to different signaling processes, e.g. representing and/orpertaining to one or more such processes and/or correspondinginformation. An indication may comprise signaling, and/or a plurality ofsignals and/or messages and/or may be comprised therein, which may betransmitted on different carriers and/or be associated to differentacknowledgement signaling processes, e.g. representing and/or pertainingto one or more such processes. Signaling associated to a channel may betransmitted such that represents signaling and/or information for thatchannel, and/or that the signaling is interpreted by the transmitterand/or receiver to belong to that channel. Such signaling may generallycomply with transmission parameters and/or format/s for the channel.

An antenna arrangement may comprise one or more antenna elements(radiating elements), which may be combined in antenna arrays. Anantenna array or subarray may comprise one antenna element, or aplurality of antenna elements, which may be arranged e.g. twodimensionally (for example, a panel) or three dimensionally. It may beconsidered that each antenna array or subarray or element is separatelycontrollable, respectively that different antenna arrays arecontrollable separately from each other. A single antennaelement/radiator may be considered the smallest example of a subarray.Examples of antenna arrays comprise one or more multi-antenna panels orone or more individually controllable antenna elements. An antennaarrangement may comprise a plurality of antenna arrays. It may beconsidered that an antenna arrangement is associated to a (specificand/or single) radio node, e.g. a configuring or informing or schedulingradio node, e.g. to be controlled or controllable by the radio node. Anantenna arrangement associated to a UE or terminal may be smaller (e.g.,in size and/or number of antenna elements or arrays) than the antennaarrangement associated to a network node. Antenna elements of an antennaarrangement may be configurable for different arrays, e.g. to change thebeamforming characteristics. In particular, antenna arrays may be formedby combining one or more independently or separately controllableantenna elements or subarrays. The beams may be provided by analogbeamforming, or in some variants by digital beamforming, or by hybridbeamforming combing analog and digital beamforming. The informing radionodes may be configured with the manner of beam transmission, e.g. bytransmitting a corresponding indicator or indication, for example asbeam identify indication. However, there may be considered cases inwhich the informing radio node/s are not configured with suchinformation, and/or operate transparently, not knowing the way ofbeamforming used. An antenna arrangement may be considered separatelycontrollable in regard to the phase and/or amplitude/power and/or gainof a signal feed to it for transmission, and/or separately controllableantenna arrangements may comprise an independent or separate transmitand/or receive unit and/or ADC (Analog-Digital-Converter, alternativelyan ADC chain) or DCA (Digital-to-Analog Converter, alternatively a DCAchain) to convert digital control information into an analog antennafeed for the whole antenna arrangement (the ADC/DCA may be consideredpart of, and/or connected or connectable to, antenna circuitry) or viceversa. A scenario in which an ADC or DCA is controlled directly forbeamforming may be considered an analog beamforming scenario; suchcontrolling may be performed after encoding/decoding and7or aftermodulation symbols have been mapped to resource elements. This may be onthe level of antenna arrangements using the same ADC/DCA, e.g. oneantenna element or a group of antenna elements associated to the sameADC/DCA. Digital beamforming may correspond to a scenario in whichprocessing for beamforming is provided before feeding signaling to theADC/DCA, e.g. by using one or more precoder/s and/or by precodinginformation, for example before and/or when mapping modulation symbolsto resource elements. Such a precoder for beamforming may provideweights, e.g. for amplitude and/or phase, and/or may be based on a(precoder) codebook, e.g. selected from a codebook. A precoder maypertain to one beam or more beams, e.g. defining the beam or beams. Thecodebook may be configured or configurable, and/or be predefined. DFTbeamforming may be considered a form of digital beamforming, wherein aDFT procedure is used to form one or more beams. Hybrid forms ofbeamforming may be considered.

A beam may be defined by a spatial and/or angular and/or spatial angulardistribution of radiation and/or a spatial angle (also referred to assolid angle) or spatial (solid) angle distribution into which radiationis transmitted (for transmission beamforming) or from which it isreceived (for reception beamforming). Reception beamforming may compriseonly accepting signals coming in from a reception beam (e.g., usinganalog beamforming to not receive outside reception beam/s), and/orsorting out signals that do not come in in a reception beam, e.g. indigital postprocessing, e.g. digital beamforming. A beam may have asolid angle equal to or smaller than 4*pi sr (4*pi correspond to a beamcovering all directions), in particular smaller than 2*pi, or pi, orpi/2, or pi/4 or pi/8 or pi/16. In particular for high frequencies,smaller beams may be used. Different beams may have different directionsand/or sizes (e.g., solid angle and/or reach). A beam may have a maindirection, which may be defined by a main lobe (e.g., center of the mainlobe, e.g. pertaining to signal strength and/or solid angle, which maybe averaged and/or weighted to determine the direction), and may haveone or more sidelobes. A lobe may generally be defined to have acontinuous or contiguous distribution of energy and/or power transmittedand/or received, e.g. bounded by one or more contiguous or contiguousregions of zero energy (or practically zero energy). A main lobe maycomprise the lobe with the largest signal strength and/or energy and/orpower content. However, sidelobes usually appear due to limitations ofbeamforming, some of which may carry signals with significant strength,and may cause multi-path effects. A sidelobe may generally have adifferent direction than a main lobe and/or other side lobes, however,due to reflections a sidelobe still may contribute to transmitted and/orreceived energy or power. A beam may be swept and/or switched over time,e.g., such that its (main) direction is changed, but its shape(angular/solid angle distribution) around the main direction is notchanged, e.g. from the transmitter's views for a transmission beam, orthe receiver's view for a reception beam, respectively. Sweeping maycorrespond to continuous or near continuous change of main direction(e.g., such that after each change, the main lobe from before the changecovers at least partly the main lobe after the change, e.g. at least to50 or 75 or 90 percent). Switching may correspond to switching directionnon-continuously, e.g. such that after each change, the main lobe frombefore the change does not cover the main lobe after the change, e.g. atmost to 50 or 25 or 10 percent.

In some cases, to one or more beams or signals or signalings may beassociated a Quasi-CoLocation (QCL) characteristic or set ofcharacteristics, or QCL class (also referred to as QCL type) or QCLidentity; beams or signal or signalings sharing such may be consideredto be Quasi-Colocated. Quasi-Colocated beams or signals or signalingsmay be considered (e.g., by a receiver) as the same beam or originatingfrom the same transmitter or transmission source, at least in regard tothe QCL characteristic or set or class or identity, and/or to share thecharacteristic/s. QCL characteristics may pertain to propagation ofsignaling, and/or one or more delay characteristics, and/or pathloss,and/or signal quality, and/or signal strength, and/or beam direction,and/or beam shape (in particular, angle or area, e.g. area of coverage),and/or Doppler shift, and/or Doppler spread, and/or delay spread, and/ortime synchronisation, and/or frequency synchronisation, and/or one ormore other parameters, e.g. pertaining to a propagation channel and/orspatial RX parameter/s (which may refer to reception beam and/ortransmission beam, e.g. shape or coverage or direction). A QCLcharacteristic may pertain to a specific channel (e.g., physical layerchannel like a control channel or data channel) and/or referencesignaling type and/or antenna port. Different QCL classes or types maypertain to different QCL characteristics or sets of characteristics; aQCL class may define and/or pertain to one or more criteria and/orthresholds and/or ranges for one or more QCL characteristics beams haveto fulfill to be considered Quasi-Colocated according to this class; aQCL identity may refer to and/or represent all beams beingquasi-colocated, according to a QCL class. Different classes may pertainto one or more of the same characteristics (e.g., different classes mayhave different criteria and/or thresholds and/or ranges for one or morecharacteristics) and/or to different characteristics. A QCL indicationmay be seen as a form of beam indication, e.g. pertaining to all beamsbelonging to one QCL class and/or QCL identity and/or quasi-colocatedbeams. A QCL identity may be indicated by a QCL indication. In somecases, a beam, and/or a beam indication, may be considered to referand/or represent a to a QCL identity, and/or to representquasi-colocated beams or signals or signalings. To a QCL identity, theremay be associated one or more ports, e.g. for one or more referencesignaling types, e.g. DM-RS and/or CSI-RS and/or PT-RS. A QCI class oridentity may be indicated by, and/or represented by, and/or beassociated to a Transmission Configuration Indicator (TCI), which may beindicated with control signaling, e.g. in a DCI.

Transmission on multiple layers (multi-layer transmission) may refer totransmission of communication signaling and/or reference signalingsimultaneously in one or more beams and/or using a plurality oftransmission sources, e.g. controlled by one network node or onewireless device. The layers may refer to layers of transmission; a layermay be considered to represent one data or signaling stream. Differentlayers may carry different data and/or data streams, e.g., to increasedata throughput. In some cases, the same data or data stream may betransported on different layers, e.g. to increase reliability.Multi-layer transmission may provide diversity, e.g. transmissiondiversity and/or spatial diversity. It may be considered thatmulti-layer transmission comprises 2, or more than 2 layers; the numberof layers of transmission may be represented by a rank or rankindication.

Signal strength may be a representation of signal power and/or signalenergy, e.g. as seen from a transmitting node or a receiving node. Abeam with larger strength at transmission (e.g., according to thebeamforming used) than another beam does may not necessarily have largerstrength at the receiver, and vice versa, for example due tointerference and/or obstruction and/or dispersion and/or absorptionand/or reflection and/or attrition or other effects influencing a beamor the signaling it carries. Signal quality may in general be arepresentation of how well a signal may be received over noise and/orinterference. A beam with better signal quality than another beam doesnot necessarily have a larger beam strength than the other beam. Signalquality may be represented for example by SIR, SNR, SINR, BER, BLER,Energy per resource element over noise/interference or anothercorresponding quality measure. Signal quality and/or signal strength maypertain to, and/or may be measured with respect to, a beam, and/orspecific signaling carried by the beam, e.g. reference signaling and/ora specific channel, e.g. a data channel or control channel. Signalstrength may be represented by received signal strength (e.g., as RSRP),and/or relative signal strength, e.g. in comparison to a referencesignal (strength), or Energy per resource element or a transmitterpower.

Uplink or sidelink signaling may be OFDMA (Orthogonal Frequency DivisionMultiple Access) or SC-FDMA (Single Carrier Frequency Division MultipleAccess) signaling. Downlink signaling may in particular be OFDMAsignaling. However, signaling is not limited thereto (Filter-Bank basedsignaling and/or Single-Carrier based signaling, e.g. SC-FDE signaling,may be considered alternatives).

A radio node may generally be considered a device or node adapted forwireless and/or radio (and/or millimeter wave) frequency communication,and/or for communication utilising an air interface, e.g. according to acommunication standard.

A radio node may be a network node, or a user equipment or terminal. Anetwork node may be any radio node of a wireless communication network,e.g. a base station and/or gNodeB (gNB) and/or eNodeB (eNB) and/or relaynode and/or micro/nano/pico/femto node and/or transmission point (TP)and/or access point (AP) and/or other node, in particular for a RAN orother wireless communication network as described herein.

The terms user equipment (UE) and terminal may be considered to beinterchangeable in the context of this disclosure. A wireless device,user equipment or terminal may represent an end device for communicationutilising the wireless communication network, and/or be implemented as auser equipment according to a standard. Examples of user equipments maycomprise a phone like a smartphone, a personal communication device, amobile phone or terminal, a computer, in particular laptop, a sensor ormachine with radio capability (and/or adapted for the air interface), inparticular for MTC (Machine-Type-Communication, sometimes also referredto M2M, Machine-To-Machine), or a vehicle adapted for wirelesscommunication. A user equipment or terminal may be mobile or stationary.A wireless device generally may comprise, and/or be implemented as,processing circuitry and/or radio circuitry, which may comprise one ormore chips or sets of chips. The circuitry and/or circuitries may bepackaged, e.g. in a chip housing, and/or may have one or more physicalinterfaces to interact with other circuitry and/or for power supply.Such a wireless device may be intended for use in a user equipment orterminal.

A radio node may generally comprise processing circuitry and/or radiocircuitry. A radio node, in particular a network node, may in some casescomprise cable circuitry and/or communication circuitry, with which itmay be connected or connectable to another radio node and/or a corenetwork.

Circuitry may comprise integrated circuitry. Processing circuitry maycomprise one or more processors and/or controllers (e.g.,microcontrollers), and/or ASICs (Application Specific IntegratedCircuitry) and/or FPGAs (Field Programmable Gate Array), or similar. Itmay be considered that processing circuitry comprises, and/or is(operatively) connected or connectable to one or more memories or memoryarrangements. A memory arrangement may comprise one or more memories. Amemory may be adapted to store digital information. Examples formemories comprise volatile and non-volatile memory, and/or Random AccessMemory (RAM), and/or Read-Only-Memory (ROM), and/or magnetic and/oroptical memory, and/or flash memory, and/or hard disk memory, and/orEPROM or EEPROM (Erasable Programmable ROM or Electrically ErasableProgrammable ROM).

Radio circuitry may comprise one or more transmitters and/or receiversand/or transceivers (a transceiver may operate or be operable astransmitter and receiver, and/or may comprise joint or separatedcircuitry for receiving and transmitting, e.g. in one package orhousing), and/or may comprise one or more amplifiers and/or oscillatorsand/or filters, and/or may comprise, and/or be connected or connectableto antenna circuitry and/or one or more antennas and/or antenna arrays.An antenna array may comprise one or more antennas, which may bearranged in a dimensional array, e.g. 2D or 3D array, and/or antennapanels. A remote radio head (RRH) may be considered as an example of anantenna array. However, in some variants, an RRH may be also beimplemented as a network node, depending on the kind of circuitry and/orfunctionality implemented therein.

Communication circuitry may comprise radio circuitry and/or cablecircuitry. Communication circuitry generally may comprise one or moreinterfaces, which may be air interface/s and/or cable interface/s and/oroptical interface/s, e.g. laser-based. Interface/s may be in particularpacket-based. Cable circuitry and/or a cable interfaces may comprise,and/or be connected or connectable to, one or more cables (e.g., opticalfiber-based and/or wire-based), which may be directly or indirectly(e.g., via one or more intermediate systems and/or interfaces) beconnected or connectable to a target, e.g. controlled by communicationcircuitry and/or processing circuitry.

Any one or any combination or all of modules disclosed herein may beimplemented in software and/or firmware and/or hardware. Differentmodules may be associated to different components of a radio node, e.g.different circuitries, or different parts of a circuitry. It may beconsidered that a module is distributed over different components and/orcircuitries. A program product as described herein may comprise themodules related to a device on which the program product is intended(e.g., a user equipment or network node) to be executed (the executionmay be performed on, and/or controlled by the associated circuitry).

A wireless communication network may be or comprise a radio accessnetwork and/or a backhaul network (e.g. a relay or backhaul network oran IAB network), and/or a Radio Access Network (RAN) in particularaccording to a communication standard. A communication standard may inparticular a standard according to 3GPP and/or 5G, e.g. according to NRor LTE, in particular LTE Evolution.

A wireless communication network may be and/or comprise a Radio AccessNetwork (RAN), which may be and/or comprise any kind of cellular and/orwireless radio network, which may be connected or connectable to a corenetwork. The approaches described herein are particularly suitable for a5G network, e.g. LTE Evolution and/or NR (New Radio), respectivelysuccessors thereof. A RAN may comprise one or more network nodes, and/orone or more terminals, and/or one or more radio nodes. A network nodemay in particular be a radio node adapted for radio and/or wirelessand/or cellular communication with one or more terminals. A terminal maybe any device adapted for radio and/or wireless and/or cellularcommunication with or within a RAN, e.g. a user equipment (UE) or mobilephone or smartphone or computing device or vehicular communicationdevice or device for machine-type-communication (MTC), etc. A terminalmay be mobile, or in some cases stationary. A RAN or a wirelesscommunication network may comprise at least one network node and a UE,or at least two radio nodes. There may be generally considered awireless communication network or system, e.g. a RAN or RAN system,comprising at least one radio node, and/or at least one network node andat least one terminal.

Transmitting in downlink may pertain to transmission from the network ornetwork node to the terminal. Transmitting in uplink may pertain totransmission from the terminal to the network or network node.Transmitting in sidelink may pertain to (direct) transmission from oneterminal to another. Uplink, downlink and sidelink (e.g., sidelinktransmission and reception) may be considered communication directions.In some variants, uplink and downlink may also be used to describedwireless communication between network nodes, e.g. for wireless backhauland/or relay communication and/or (wireless) network communication forexample between base stations or similar network nodes, in particularcommunication terminating at such. It may be considered that backhauland/or relay communication and/or network communication is implementedas a form of sidelink or uplink communication or similar thereto.

Control information or a control information message or correspondingsignaling (control signaling) may be transmitted on a control channel,e.g. a physical control channel, which may be a downlink channel or (ora sidelink channel in some cases, e.g. one UE scheduling another UE).For example, control information/allocation information may be signaledby a network node on PDCCH (Physical Downlink Control Channel) and/or aPDSCH (Physical Downlink Shared Channel) and/or a HARQ-specific channel.Acknowledgement signaling, e.g. as a form of control information orsignaling like uplink control information/signaling, may be transmittedby a terminal on a PUCCH (Physical Uplink Control Channel) and/or PUSCH(Physical Uplink Shared Channel) and/or a HARQ-specific channel.Multiple channels may apply for multi-component/multi-carrier indicationor signaling.

Scheduling may comprise indicating, e.g. with control signaling like DCIor SCI signaling and/or signaling on a control channel like PDCCH orPSCCH, one or more scheduling opportunities of a configuration intendedto carry data signaling or subject signaling. The configuration may berepresented or representable by, and/or correspond to, a table. Ascheduling assignment may for example point to an opportunity of thereception allocation configuration, e.g. indexing a table of schedulingopportunities. In some cases, a reception allocation configuration maycomprise 15 or 16 scheduling opportunities. The configuration may inparticular represent allocation in time. It may be considered that thereception allocation configuration pertains to data signaling, inparticular on a physical data channel like PDSCH or PSSCH. In general,the reception allocation configuration may pertain to downlinksignaling, or in some scenarios to sidelink signaling. Control signalingscheduling subject transmission like data signaling may point and/orindex and/or refer to and/or indicate a scheduling opportunity of thereception allocation configuration. It may be considered that thereception allocation configuration is configured or configurable withhigher-layer signaling, e.g. RRC or MAC layer signaling. The receptionallocation configuration may be applied and/or applicable and/or validfor a plurality of transmission timing intervals, e.g. such that foreach interval, one or more opportunities may be indicated or allocatedfor data signaling. These approaches allow efficient and flexiblescheduling, which may be semi-static, but may updated or reconfigured onuseful timescales in response to changes of operation conditions.

Signaling may generally be considered to represent an electromagneticwave structure (e.g., over a time interval and frequency interval),which is intended to convey information to at least one specific orgeneric (e.g., anyone who might pick up the signaling) target. A processof signaling may comprise transmitting the signaling. Transmittingsignaling, in particular control signaling or communication signaling,e.g. comprising, or representing acknowledgement signaling and/orresource requesting information, may comprise encoding and/ormodulating. Encoding and/or modulating may comprise error detectioncoding and/or forward error correction encoding and/or scrambling.Receiving signaling like control signaling or data signaling maycomprise corresponding decoding and/or demodulation, e.g. based onreference signaling associated to the signaling to be received. Errordetection coding may comprise, and/or be based on, parity or checksumapproaches, e.g. CRC (Cyclic Redundancy Check). Forward error correctioncoding may comprise and/or be based on for example turbo coding and/orReed-Muller coding, and/or polar coding and/or LDPC coding (Low DensityParity Check). The type of coding used may be based on the channel(e.g., physical channel) the coded signal is associated to. A code ratemay represent the ratio of the number of information bits beforeencoding to the number of encoded bits after encoding, considering thatencoding adds coding bits for error detection coding and forward errorcorrection. Coded bits may refer to information bits (also calledsystematic bits) plus coding bits.

Communication signaling may comprise, and/or represent, and/or beimplemented as, data signaling, and/or user plane signaling.Communication signaling may be associated to a data channel, e.g. aphysical downlink channel or physical uplink channel or physicalsidelink channel, in particular a PDSCH (Physical Downlink SharedChannel) or PSSCH (Physical Sidelink Shared Channel). Generally, a datachannel may be a shared channel or a dedicated channel. Data signalingmay be signaling associated to and/or on a data channel.

An indication generally may explicitly and/or implicitly indicate theinformation it represents and/or indicates. Implicit indication may forexample be based on position and/or resource used for transmission.Explicit indication may for example be based on a parametrisation withone or more parameters, and/or one or more index or indices, and/or oneor more bit patterns representing the information. It may in particularbe considered that control signaling as described herein, based on theutilised resource sequence, implicitly indicates the control signalingtype.

A resource element may generally describe the smallest individuallyusable and/or encodable and/or decodable and/or modulatable and/ordemodulatable time-frequency resource, and/or may describe atime-frequency resource covering a symbol time length in time and asubcarrier in frequency. A signal may be allocatable and/or allocated toa resource element. A subcarrier may be a subband of a carrier, e.g. asdefined by a standard. A carrier may define a frequency and/or frequencyband for transmission and/or reception. In some variants, a signal(jointly encoded/modulated) may cover more than one resource elements. Aresource element may generally be as defined by a correspondingstandard, e.g. NR or LTE. As symbol time length and/or subcarrierspacing (and/or numerology) may be different between different symbolsand/or subcarriers, different resource elements may have differentextension (length/width) in time and/or frequency domain, in particularresource elements pertaining to different carriers.

A resource generally may represent a time-frequency and/or coderesource, on which signaling, e.g. according to a specific format, maybe communicated, for example transmitted and/or received, and/or beintended for transmission and/or reception.

A border symbol (or allocation unit) may generally represent a startingsymbol (allocation unit) or an ending symbol (allocation unit) fortransmitting and/or receiving. A starting symbol (or allocation unit)may in particular be a starting symbol of uplink or sidelink signaling,for example control signaling or data signaling. Such signaling may beon a data channel or control channel, e.g. a physical channel, inparticular a physical uplink shared channel (like PUSCH) or a sidelinkdata or shared channel, or a physical uplink control channel (likePUCCH) or a sidelink control channel. If the starting symbol (orallocation unit) is associated to control signaling (e.g., on a controlchannel), the control signaling may be in response to received signaling(in sidelink or downlink), e.g. representing acknowledgement signalingassociated thereto, which may be HARQ or ARQ signaling. An ending symbol(or allocation unit) may represent an ending symbol (in time) ofdownlink or sidelink transmission or signaling, which may be intended orscheduled for the radio node or user equipment. Such downlink signalingmay in particular be data signaling, e.g. on a physical downlink channellike a shared channel, e.g. a PDSCH (Physical Downlink Shared Channel).A starting symbol (or allocation unit) may be determined based on,and/or in relation to, such an ending symbol (or allocation unit).

Configuring a radio node, in particular a terminal or user equipment,may refer to the radio node being adapted or caused or set and/orinstructed to operate according to the configuration. Configuring may bedone by another device, e.g., a network node (for example, a radio nodeof the network like a base station or eNodeB) or network, in which caseit may comprise transmitting configuration data to the radio node to beconfigured. Such configuration data may represent the configuration tobe configured and/or comprise one or more instruction pertaining to aconfiguration, e.g. a configuration for transmitting and/or receiving onallocated resources, in particular frequency resources. A radio node mayconfigure itself, e.g., based on configuration data received from anetwork or network node. A network node may utilise, and/or be adaptedto utilise, its circuitry/ies for configuring. Allocation informationmay be considered a form of configuration data. Configuration data maycomprise and/or be represented by configuration information, and/or oneor more corresponding indications and/or message/s

Generally, configuring may include determining configuration datarepresenting the configuration and providing, e.g. transmitting, it toone or more other nodes (parallel and/or sequentially), which maytransmit it further to the radio node (or another node, which may berepeated until it reaches the wireless device). Alternatively, oradditionally, configuring a radio node, e.g., by a network node or otherdevice, may include receiving configuration data and/or data pertainingto configuration data, e.g., from another node like a network node,which may be a higher-level node of the network, and/or transmittingreceived configuration data to the radio node. Accordingly, determininga configuration and transmitting the configuration data to the radionode may be performed by different network nodes or entities, which maybe able to communicate via a suitable interface, e.g., an X2 interfacein the case of LTE or a corresponding interface for NR. Configuring aterminal may comprise scheduling downlink and/or uplink transmissionsfor the terminal, e.g. downlink data and/or downlink control signalingand/or DCI and/or uplink control or data or communication signaling, inparticular acknowledgement signaling, and/or configuring resourcesand/or a resource pool therefor.

A resource structure may be considered to be neighbored in frequencydomain by another resource structure, if they share a common borderfrequency, e.g. one as an upper frequency border and the other as alower frequency border. Such a border may for example be represented bythe upper end of a bandwidth assigned to a subcarrier n, which alsorepresents the lower end of a bandwidth assigned to a subcarrier n+1. Aresource structure may be considered to be neighbored in time domain byanother resource structure, if they share a common border time, e.g. oneas an upper (or right in the figures) border and the other as a lower(or left in the figures) border. Such a border may for example berepresented by the end of the symbol time interval assigned to a symboln, which also represents the beginning of a symbol time intervalassigned to a symbol n+1.

Generally, a resource structure being neighbored by another resourcestructure in a domain may also be referred to as abutting and/orbordering the other resource structure in the domain.

A resource structure may in general represent a structure in time and/orfrequency domain, in particular representing a time interval and afrequency interval. A resource structure may comprise and/or becomprised of resource elements, and/or the time interval of a resourcestructure may comprise and/or be comprised of symbol time interval/s,and/or the frequency interval of a resource structure may compriseand/or be comprised of subcarrier/s. A resource element may beconsidered an example for a resource structure, a slot or mini-slot or aPhysical Resource Block (PRB) or parts thereof may be considered others.A resource structure may be associated to a specific channel, e.g. aPUSCH or PUCCH, in particular resource structure smaller than a slot orPRB.

Examples of a resource structure in frequency domain comprise abandwidth or band, or a bandwidth part. A bandwidth part may be a partof a bandwidth available for a radio node for communicating, e.g. due tocircuitry and/or configuration and/or regulations and/or a standard. Abandwidth part may be configured or configurable to a radio node. Insome variants, a bandwidth part may be the part of a bandwidth used forcommunicating, e.g. transmitting and/or receiving, by a radio node. Thebandwidth part may be smaller than the bandwidth (which may be a devicebandwidth defined by the circuitry/configuration of a device, and/or asystem bandwidth, e.g. available for a RAN). It may be considered that abandwidth part comprises one or more resource blocks or resource blockgroups, in particular one or more PRBs or PRB groups. A bandwidth partmay pertain to, and/or comprise, one or more carriers. A resourcestructure may in time domain comprise and/or represent a time interval,e.g. one of more allocation units and/or symbols and/or slots and/orsubframes. In general, any reference to a symbol as a time interval maybe considered as a reference to an allocation unit as a more generalterm, unless the reference to the symbol is specific, e.g. referring toa specific division or modulation technique, or to modulation symbols astransmission structures.

A carrier may generally represent a frequency range or band and/orpertain to a central frequency and an associated frequency interval. Itmay be considered that a carrier comprises a plurality of subcarriers. Acarrier may have assigned to it a central frequency or center frequencyinterval, e.g. represented by one or more subcarriers (to eachsubcarrier there may be generally assigned a frequency bandwidth orinterval). Different carriers may be non-overlapping, and/or may beneighboring in frequency domain.

It should be noted that the term “radio” in this disclosure may beconsidered to pertain to wireless communication in general, and may alsoinclude wireless communication utilising millimeter waves, in particularabove one of the thresholds 10 GHz or 20 GHz or 50 GHz or 52 GHz or 52.6GHz or 60 GHz or 72 GHz or 100 GHz or 114 GHz. Such communication mayutilise one or more carriers, e.g. in FDD and/or carrier aggregation.Upper frequency boundaries may correspond to 300 GHz or 200 GHz or 120GHz or any of the thresholds larger than the one representing the lowerfrequency boundary.

A radio node, in particular a network node or a terminal, may generallybe any device adapted for transmitting and/or receiving radio and/orwireless signals and/or data, in particular communication data, inparticular on at least one carrier. The at least one carrier maycomprise a carrier accessed based on an LBT procedure (which may becalled LBT carrier), e.g., an unlicensed carrier. It may be consideredthat the carrier is part of a carrier aggregate.

Receiving or transmitting on a cell or carrier may refer to receiving ortransmitting utilizing a frequency (band) or spectrum associated to thecell or carrier. A cell may generally comprise and/or be defined by orfor one or more carriers, in particular at least one carrier for ULcommunication/transmission (called UL carrier) and at least one carrierfor DL communication/transmission (called DL carrier). It may beconsidered that a cell comprises different numbers of UL carriers and DLcarriers. Alternatively, or additionally, a cell may comprise at leastone carrier for UL communication/transmission and DLcommunication/transmission, e.g., in TDD-based approaches.

A channel may generally be a logical, transport or physical channel. Achannel may comprise and/or be arranged on one or more carriers, inparticular a plurality of subcarriers. A channel carrying and/or forcarrying control signaling/control information may be considered acontrol channel, in particular if it is a physical layer channel and/orif it carries control plane information. Analogously, a channel carryingand/or for carrying data signaling/user information may be considered adata channel, in particular if it is a physical layer channel and/or ifit carries user plane information. A channel may be defined for aspecific communication direction, or for two complementary communicationdirections (e.g., UL and DL, or sidelink in two directions), in whichcase it may be considered to have two component channels, one for eachdirection. Examples of channels comprise a channel for low latencyand/or high reliability transmission, in particular a channel forUltra-Reliable Low Latency Communication (URLLC), which may be forcontrol and/or data.

In general, a symbol may represent and/or be associated to a symbol timelength, which may be dependent on the carrier and/or subcarrier spacingand/or numerology of the associated carrier. Accordingly, a symbol maybe considered to indicate a time interval having a symbol time length inrelation to frequency domain. A symbol time length may be dependent on acarrier frequency and/or bandwidth and/or numerology and/or subcarrierspacing of, or associated to, a symbol. Accordingly, different symbolsmay have different symbol time lengths. In particular, numerologies withdifferent subcarrier spacings may have different symbol time length.Generally, a symbol time length may be based on, and/or include, a guardtime interval or cyclic extension, e.g. prefix or postfix.

A sidelink may generally represent a communication channel (or channelstructure) between two UEs and/or terminals, in which data istransmitted between the participants (UEs and/or terminals) via thecommunication channel, e.g. directly and/or without being relayed via anetwork node. A sidelink may be established only and/or directly via airinterface/s of the participant, which may be directly linked via thesidelink communication channel. In some variants, sidelink communicationmay be performed without interaction by a network node, e.g. on fixedlydefined resources and/or on resources negotiated between theparticipants. Alternatively, or additionally, it may be considered thata network node provides some control functionality, e.g. by configuringresources, in particular one or more resource pool/s, for sidelinkcommunication, and/or monitoring a sidelink, e.g. for charging purposes.

Sidelink communication may also be referred to as device-to-device (D2D)communication, and/or in some cases as ProSe (Proximity Services)communication, e.g. in the context of LTE. A sidelink may be implementedin the context of V2x communication (Vehicular communication), e.g. V2V(Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure) and/or V2P(Vehicle-to-Person). Any device adapted for sidelink communication maybe considered a user equipment or terminal.

A sidelink communication channel (or structure) may comprise one or more(e.g., physical or logical) channels, e.g. a PSCCH (Physical SidelinkControl CHannel, which may for example carry control information like anacknowledgement position indication, and/or a PSSCH (Physical SidelinkShared CHannel, which for example may carry data and/or acknowledgementsignaling). It may be considered that a sidelink communication channel(or structure) pertains to and/or used one or more carrier/s and/orfrequency range/s associated to, and/or being used by, cellularcommunication, e.g. according to a specific license and/or standard.Participants may share a (physical) channel and/or resources, inparticular in frequency domain and/or related to a frequency resourcelike a carrier) of a sidelink, such that two or more participantstransmit thereon, e.g. simultaneously, and/or time-shifted, and/or theremay be associated specific channels and/or resources to specificparticipants, so that for example only one participant transmits on aspecific channel or on a specific resource or specific resources, e.g.,in frequency domain and/or related to one or more carriers orsubcarriers.

A sidelink may comply with, and/or be implemented according to, aspecific standard, e.g. an LTE-based standard and/or NR. A sidelink mayutilise TDD (Time Division Duplex) and/or FDD (Frequency DivisionDuplex) technology, e.g. as configured by a network node, and/orpreconfigured and/or negotiated between the participants. A userequipment may be considered to be adapted for sidelink communication ifit, and/or its radio circuitry and/or processing circuitry, is adaptedfor utilising a sidelink, e.g. on one or more frequency ranges and/orcarriers and/or in one or more formats, in particular according to aspecific standard. It may be generally considered that a Radio AccessNetwork is defined by two participants of a sidelink communication.Alternatively, or additionally, a Radio Access Network may berepresented, and/or defined with, and/or be related to a network nodeand/or communication with such a node.

Communication or communicating may generally comprise transmittingand/or receiving signaling. Communication on a sidelink (or sidelinksignaling) may comprise utilising the sidelink for communication(respectively, for signaling). Sidelink transmission and/or transmittingon a sidelink may be considered to comprise transmission utilising thesidelink, e.g. associated resources and/or transmission formats and/orcircuitry and/or the air interface. Sidelink reception and/or receivingon a sidelink may be considered to comprise reception utilising thesidelink, e.g. associated resources and/or transmission formats and/orcircuitry and/or the air interface. Sidelink control information (e.g.,SCI) may generally be considered to comprise control informationtransmitted utilising a sidelink.

A transmission may generally pertain to a specific channel and/orspecific resources, in particular with a starting symbol and endingsymbol in time, covering the interval therebetween. A scheduledtransmission may be a transmission scheduled and/or expected and/or forwhich resources are scheduled or provided or reserved. However, notevery scheduled transmission has to be realized. For example, ascheduled downlink transmission may not be received, or a scheduleduplink transmission may not be transmitted due to power limitations, orother influences (e.g., a channel on an unlicensed carrier beingoccupied). A transmission may be scheduled for a transmission timingsubstructure (e.g., a mini-slot, and/or covering only a part of atransmission timing structure) within a transmission timing structurelike a slot. A border symbol may be indicative of a symbol in thetransmission timing structure at which the transmission starts or ends.

Predefined in the context of this disclosure may refer to the relatedinformation being defined for example in a standard, and/or beingavailable without specific configuration from a network or network node,e.g. stored in memory, for example independent of being configured.Configured or configurable may be considered to pertain to thecorresponding information being set/configured, e.g. by the network or anetwork node.

A configuration or schedule, like a mini-slot configuration and/orstructure configuration, may schedule transmissions, e.g. for thetime/transmissions it is valid, and/or transmissions may be scheduled byseparate signaling or separate configuration, e.g. separate RRCsignaling and/or downlink control information signaling. Thetransmission/s scheduled may represent signaling to be transmitted bythe device for which it is scheduled, or signaling to be received by thedevice for which it is scheduled, depending on which side of acommunication the device is. It should be noted that downlink controlinformation or specifically DCI signaling may be considered physicallayer signaling, in contrast to higher layer signaling like MAC (MediumAccess Control) signaling or RRC layer signaling. The higher the layerof signaling is, the less frequent/the more time/resource consuming itmay be considered, at least partially due to the information containedin such signaling having to be passed on through several layers, eachlayer requiring processing and handling.

A scheduled transmission, and/or transmission timing structure like amini-slot or slot, may pertain to a specific channel, in particular aphysical uplink shared channel, a physical uplink control channel, or aphysical downlink shared channel, e.g. PUSCH, PUCCH or PDSCH, and/or maypertain to a specific cell and/or carrier aggregation. A correspondingconfiguration, e.g. scheduling configuration or symbol configuration maypertain to such channel, cell and/or carrier aggregation. It may beconsidered that the scheduled transmission represents transmission on aphysical channel, in particular a shared physical channel, for example aphysical uplink shared channel or physical downlink shared channel. Forsuch channels, semi-persistent configuring may be particularly suitable.

Generally, a configuration may be a configuration indicating timing,and/or be represented or configured with corresponding configurationdata. A configuration may be embedded in, and/or comprised in, a messageor configuration or corresponding data, which may indicate and/orschedule resources, in particular semi-persistently and/orsemi-statically.

A control region of a transmission timing structure may be an intervalin time and/or frequency domain for intended or scheduled or reservedfor control signaling, in particular downlink control signaling, and/orfor a specific control channel, e.g. a physical downlink control channellike PDCCH. The interval may comprise, and/or consist of, a number ofsymbols in time, which may be configured or configurable, e.g. by(UE-specific) dedicated signaling (which may be single-cast, for exampleaddressed to or intended for a specific UE), e.g. on a PDCCH, or RRCsignaling, or on a multicast or broadcast channel. In general, thetransmission timing structure may comprise a control region covering aconfigurable number of symbols. It may be considered that in general theborder symbol is configured to be after the control region in time. Acontrol region may be associated, e.g. via configuration and/ordetermination, to one or more specific UEs and/or formats of PDCCHand/or DCI and/or identifiers, e.g. UE identifiers and/or RNTIs orcarrier/cell identifiers, and/or be represented and/or associated to aCORESET and/or a search space.

The duration of a symbol (symbol time length or interval or allocationunit) of the transmission timing structure may generally be dependent ona numerology and/or carrier, wherein the numerology and/or carrier maybe configurable. The numerology may be the numerology to be used for thescheduled transmission.

A transmission timing structure may comprise a plurality of allocationunits or symbols, and/or define an interval comprising several symbolsor allocation units (respectively their associated time intervals). Inthe context of this disclosure, it should be noted that a reference to asymbol for ease of reference may be interpreted to refer to the timedomain projection or time interval or time component or duration orlength in time of the symbol, unless it is clear from the context thatthe frequency domain component also has to be considered. Examples oftransmission timing structures include slot, subframe, mini-slot (whichalso may be considered a substructure of a slot), slot aggregation(which may comprise a plurality of slots and may be considered asuperstructure of a slot), respectively their time domain component. Atransmission timing structure may generally comprise a plurality ofsymbols and/or allocation units defining the time domain extension(e.g., interval or length or duration) of the transmission timingstructure, and arranged neighboring to each other in a numberedsequence. A timing structure (which may also be considered orimplemented as synchronisation structure) may be defined by a successionof such transmission timing structures, which may for example define atiming grid with symbols representing the smallest grid structures. Atransmission timing structure, and/or a border symbol or a scheduledtransmission may be determined or scheduled in relation to such a timinggrid. A transmission timing structure of reception may be thetransmission timing structure in which the scheduling control signalingis received, e.g. in relation to the timing grid. A transmission timingstructure may in particular be a slot or subframe or in some cases, amini-slot. In some cases, a timing structure may be represented by aframe structure. Timing structures may be associated to specifictransmitters and/or cells and/or beams and/or signalings.

Signaling utilising, and/or on and/or associated to, resources or aresource structure may be signaling covering the resources or structure,signaling on the associated frequency/ies and/or in the associated timeinterval/s. It may be considered that a signaling resource structurecomprises and/or encompasses one or more substructures, which may beassociated to one or more different channels and/or types of signalingand/or comprise one or more holes (resource element/s not scheduled fortransmissions or reception of transmissions). A resource substructure,e.g. a feedback resource structure, may generally be continuous in timeand/or frequency, within the associated intervals. It may be consideredthat a substructure, in particular a feedback resource structure,represents a rectangle filled with one or more resource elements intime/frequency space. However, in some cases, a resource structure orsubstructure, in particular a frequency resource range, may represent anon-continuous pattern of resources in one or more domains, e.g. timeand/or frequency. The resource elements of a substructure may bescheduled for associated signaling.

Example types of signaling comprise signaling of a specificcommunication direction, in particular, uplink signaling, downlinksignaling, sidelink signaling, as well as reference signaling (e.g., SRSor CRS or CSI-RS), communication signaling, control signaling, and/orsignaling associated to a specific channel like PUSCH, PDSCH, PUCCH,PDCCH, PSCCH, PSSCH, etc.).

A signaling sequence may correspond to a sequence of modulation symbols(e.g., in time domain, or in frequency domain for an OFDM system). Thesignaling sequence may be predefined, or configured or configurable,e.g. to a wireless device. For OFDM or SC-FDM, each element of asignaling sequence may be mapped to a subcarrier; in general, forSC-based signaling, a corresponding mapping in time domain may beutilised (for example, such that each element may use essentially thefull synchronisation bandwidth). A signaling sequence may comprise(ordered) modulation symbols, each modulation symbol representing avalue of the sequence it is based on, e.g. based on the modulationscheme used and/or in a phase or constellation diagram; for somesequences like Zadoff-Chu sequences, there may be a mapping betweennon-integer sequence elements and transmitted waveform, which may not berepresented in the context of a modulation scheme like BPSK or QPSK orhigher. A signaling sequence may be a physical layer signaling orsignal, which may be devoid of higher layer information. A signalingsequence may be based on a sequence, e.g. a bit sequence or symbolsequence and/or a modulation, e.g. performed on the sequence. Elementsof a signaling sequence may be mapped to frequency domain (e.g., tosubcarriers, in particular in a pattern like a comb structure or ininterlaces) and/or in time domain, e.g. to one or more allocation unitsor symbol time intervals. A DFT-s-OFDM based waveform may be a waveformconstructed by performing a DFT-spreading operation on modulationsymbols mapped to a frequency interval (e.g., subcarriers), e.g. toprovide a time-variable signal. A DFT-s-OFDM based waveform may also bereferred to a SC-FDM waveform. It may be considered to provide good PAPRcharacteristics, allowing optimised operation of power amplifiers, inparticular for high frequencies. In general, the approaches describedherein may also be applicable to Single-Carrier based waveforms, e.g.FDE-based waveforms. Communication, e.g. on data channel/s and/orcontrol channel/s, may be based on, and/o utilise, a DFT-s-OFDM basedwaveform, or a Single-Carrier based waveform.

A sequence may generally be considered to be based on a root sequence ifit can be constructed from the root sequence (or represents itdirectly), e.g. by shifting in phase and/or frequency and/or timedomain, and/or performing a cyclic shift and/or a cyclic extension,and/or copying/repeating and/or processing or operating on with a code,and/or interleaving or re-ordering of elements of the sequence, and/orextending or shortening the root sequence. A cyclic extension of asequence may comprise taking a part of the sequence (in particular aborder part like a tail or beginning) and appending it to the sequence,e.g. at the beginning or end, for example in time domain or frequencydomain. Thus, a cyclic extended sequence may represent a (root) sequenceand at least a part repetition of the (root) sequence. Operationsdescribed may be combined, in any order, in particular a shift and acyclic extension. A cyclic shift in a domain may comprise shifting thesequence in the domain within an interval, such that the total number ofsequence elements is constant, and the sequence is shifted as if theinterval represented a ring (e.g., such that starting from the samesequence element, which may appear at different location in theinterval), the order of elements is the same if the borders of theintervals are considered to be continuous, such that leaving one end ofthe interval leads to entering the interval at the other end).Processing and/or operating on with a code may correspond toconstructing a sequence out of copies of a root sequence, wherein eachcopy is multiplied and/or operated on with an element of the code.Multiplying with an element of a code may represent and/or correspond toa shift (e.g., constant, or linear or cyclic) in phase and/or frequencyand/or time domain, depending on representation. In the context of thisdisclosure, a sequence being based on and/or being constructed and/orprocessed may be any sequence that would result from such constructionor processing, even if the sequence is just read from memory. Anyisomorphic or equivalent or corresponding way to arrive at the sequenceis considered to be included by such terminology; the construction thusmay be considered to define the characteristics of the sequence and/orthe sequence, not necessarily a specific way to construct them, as theremay be multiple equivalent ways that are mathematically equivalent.Thus, a sequence “based on” or “constructed” or similar terminology maybe considered to correspond to the sequence being “represented by” or“may be represented by” or “representable as”.

A root sequence for a signaling sequence associated to one allocationunit may be basis for construction of a larger sequence. In this case,the larger sequence and/or the root sequence basis for its constructionmay be considered root sequence for signaling sequences associated toother allocation units.

For OFDM or SC-FDM, each element of a signaling sequence may be mappedto a subcarrier; in general, for SC-based signaling, a correspondingmapping in time domain may be utilised (such that each element may useessentially the full synchronisation bandwidth). A signaling sequencemay comprise (ordered) modulation symbols, each modulation symbolrepresenting a value of the sequence it is based on, e.g. based on themodulation scheme used and/or in a phase or constellation diagram; forsome sequences like Zadoff-Chu sequences, there may be a mapping betweennon-integer sequence elements and transmitted waveform, which may not berepresented in the context of a modulation scheme like BPSK or QPSK orhigher.

A signaling sequence of an allocation unit may be based on a sequenceroot, e.g. a root sequence. A sequence root in general may represent orindicate a base for deriving or determining a signaling sequence; theroot may be associated to, and/or represent a sequence directly, and/orindicate or represent a base sequence and/or seed. Examples of sequenceroots may comprise a Zadoff Chu root sequence, a sequence seed, e.g. aseed for a Gold sequence, or a Golay complimentary sequence. A signalingsequence may be derived or derivable from, and/or be based on, asequency root, e.g. based on a code, which may represent a shift oroperation or processing on the root sequence or a sequence indicated bythe sequence root, e.g. to provide the signaling sequence; the signalingsequence may be based on such shifted or processed or operated on rootsequence. The code may in particular represent a cyclic shift and/orphase shift and/or phase ramp (e.g., an amount for such). The code mayassign one operation or shift for each allocation unit.

In general, a signaling sequence associated to an allocation unit(and/or the allocation units) associated to control signaling (and/orreference signaling) may be based on a root sequence which may be aM-sequence or Zadoff-Chu sequence, or a Gold or Golay sequence, oranother sequence with suitable characteristics regarding correlationand/or interference (e.g., self-interference and/or interference withother or neighboring transmitters). Different sequences may be used asroot sequences for different signaling sequences, or the same sequencemay be used. If different sequences are used, they may be of the sametype (Gold, Golay, M- or Zadoff-Chu, for example). The (signaling and/orroot) sequences may correspond to or be time-domain sequences, e.g. timedomain Zadoff-Chu and/or time-domain M sequences.

In some cases, a shifted object like a signaling or signals or sequencesor information may be shifted, e.g. relative to a predecessor (e.g., oneis subject to a shift, and the shifted version is used), or relative toanother (e.g., one associated to one signaling or allocation unit may beshifted to another associated to a second signaling or allocation unit,both may be used). One possible way of shifting is operating a code onit, e.g. to multiply each element of a shifting object with a factor. Aramping (e.g. multiplying with a monotonously increasing or periodicfactor) may be considered an example of shifting. Another is a cyclicshift in a domain or interval. A cyclic shift (or circular shift) maycorrespond to a rearrangement of the elements in the shifting object,corresponding to moving the final element or elements to the firstposition, while shifting all other entries to the next position, or byperforming the inverse operation (such that the shifted object as theresult will have the same elements as the shifting object, in a shiftedbut similar order). Shifting in general may be specific to an intervalin a domain, e.g. an allocation unit in time domain, or a bandwidth infrequency domain. For example, it may be considered that signals ormodulation symbols in an allocation unit are shifted, such that theorder of the modulation symbols or signals is shifted in the allocationunit. In another example, allocation units may be shifted, e.g. in alarger time interval—this may leave signals in the allocation unitsunshifted with reference to the individual allocation unit, but maychange the order of the allocation units. Domains for shifting may forexample be time domain and/or phase domain and/or frequency domain.Multiple shifts in the same domain or different domains, and/or the sameinterval or different intervals (differently sized intervals, forexample) may be performed.

Reference signaling may have a type. Types of reference signaling mayinclude synchronisation signaling, and/or DM-RS (used to facilitatedemodulation of associated data signaling and/or control signaling),and/or PT-RS (used to facilitate phase tracking of associated datasignaling and/or control signaling, e.g. within a time interval orsymbol or allocation unit carrying such signaling), and/or CSI-RS (e.g.,used for channel estimation and/or reporting). It may be considered thatPT-RS are inserted into a bit sequence, or a modulation symbol sequence,which may represent data. For example, PT-RS may be mapped ontosubcarriers of a symbol also carrying data symbols. Accordingly, PT-RSinsertion may be optimised for hardware implementations. In some cases,PT-RS may be modulated differently and/or independently of themodulation symbols representing data (or data bits).

A comb structure, or short comb, may indicate a distribution, orperiodic arrangement of reference signaling, in particular in frequencyspace, e.g. between an upper and lower frequency. A comb may pertain toone FDMA symbol and/or one (the same) symbol time interval or allocationunit. A comb may have width or size N and/or may pertain to, and/or beassociated to, specific signaling and/or a type of signaling, e.g. atype of reference signaling. The width N may indicate how many emptysubcarriers are between (e.g., non-neighbouring) subcarriers carrying anelement or signal or symbol of the signaling (e.g., this number may beN−1), or how many empty subcarriers and non-empty subcarriers form apattern that is repeated in frequency domain. In general, each comb mayindicate that at least one empty subcarrier is to be between non-emptysubcarriers. In this context, empty may refer to empty regarding thepattern or distribution of the signaling associated to the comb (andnon-empty may refer to a subcarrier carrying an element or symbol of theassociated signaling); in some cases, other signalings (which may have acomb structure as well) may be carried on empty subcarriers, e.g.transmitted using other transmission sources and/or other devices,and/or mapped into the comb (e.g., for a DMRS comb, data signaling maybe mapped on subcarriers not carrying DMRS). A comb structure maygenerally describe a structure in which for every N-th (N may be aninteger) resource element and/or subcarrier a reference signal or anelement of a sequence of the reference signaling, and/or representingthe reference signaling, and/or on which the reference signaling isbased, is mapped to, and/or represented by signaling the resourceelement and/or subcarrier, in particular an element (symbol) of amodulation symbol sequence, or an element of a sequence. N may be calledthe width of the comb. Generally, the comb may indicate the periodicityof the pattern inside the frequency range of the reference signaling.The pattern may in particular pertain to one reference signal and/orresource element or subcarrier for transmitting a reference signal, suchthat the comb may be considered to indicate that on every N-th resourceelement (in particular, only there) and/or subcarrier there is to be areference signal or element of an associated sequence, and/or how manyresource elements and/or subcarriers are between resource elementsand/or subcarriers with reference signals. However, there may beconsidered variants, in which the pattern represents more than onereference signals. The pattern may also generally represent and/orindicate one or more empty signals and/or one or more data signals(respectively associated resource elements and/or subcarriers). For eachcomb or comb structure with a width of N, there may be N or f(N)different available individual combs. For example, for N=2, there may betwo combs shifted in frequency space by one, or an odd number, ofsubcarriers (e.g., based on a frequency domain offset, or a subcarrieroffset). A comb structure or comb of width of N may be indicated asN-comb. Specific combs of this width may be numbered within N. Forexample, for a 2-comb, there may be a comb 1 (or C1) and a comb 2 (orC2), which may be shifted relative to each other, e.g. to dovetail suchthat all subcarrier covered by both combs carry signaling (associated toC1 and C2 alternatingly in frequency domain).

A comb may comprise two or more, for example at least three or at leastfour, repetitions of the pattern. The comb may indicate a referenceand/or indication, e.g. a resource element and/or subcarrier, which maybe related to the upper and/or lower boundary in frequency, regardingthe arrangement and/or location in frequency of a first pattern, and/orthe relative shift of the pattern and/or comb in frequency. Generally, acomb structure may cover at least part, and/or at least the majority,and/or essentially all or all resource elements and/or subcarriers ofthe plurality of resource elements and/or subcarriers, and/or thesymbol.

A comb structure may result from combining two comb structures, whichmay in particular comb structures with pattern comprising only onereference signal. A comb structure may be determined and/or amendedbefore transmission, e.g. based on other reference signaling to betransmitted, e.g. on a different antenna port. In this context,reference signals may be replaced by empty signals to avoid overlapand/or interference. Generally, if the other reference signalingutilises a comb structure as well, a different/new comb (as acombination of combs) may be considered to be determined, e.g. with lessdense reference signal distribution and/or a different/wider pattern.Alternatively, or additionally, combs may be combined to increase thereference signal density, e.g. by combining combs with different widths,and/or with shifted offsets.

Generally, a comb structure may represent and/or comprise and/or becomprised of any of the combs/comb structures described herein.

In general, a clear channel assessment (CCA) procedure may comprisemonitoring and/or performing measurements on a frequency range and/orchannel and/or carrier and/or spectrum; in some cases a CCA proceduremay also be referred to as LBT procedure; e.g., if only one CCA isperformed for a LBT procedure. In particular, the CCA procedure maycomprise determining whether a channel or frequency range or spectrum orcarrier is occupied, for example based on one or more parameters, e.g.measured or monitored energy and/or power and/or signal strength and/orenergy density and/or power density or similar. A CCA procedure may beperformed and/or pertain to a specific time interval (also referred toas CCA duration), for example a measuring or monitoring interval overwhich measurement and/or monitoring is performed. The CCA procedure maybe performed and/or pertain to a specific frequency range (also referredto as CCA frequency range), for example a measurement and/or monitoringrange. The CCA frequency range may be part of and/or comprise thefrequency range and/or carrier and/or spectrum and/or channel to beaccessed (which may be referred to as access target frequency range, oraccess target in short; accessing in this context may be considered torefer to transmitting signaling on the range and/or carrier and/orspectrum). The CCA frequency range may be considered representative ofthe access target frequency range in terms of occupation status(occupied or non-occupied). A CCA procedure may indicate whether theaccess target is occupied or not, for example by comparing measurementresults with one or more threshold values. For example, if the measuredpower or energy over the CCA duration is lower than an occupancythreshold, the access target may be considered unoccupied; if it reachesor is higher than the threshold, it may be considered occupied. Adetermination as unoccupied may be considered a positive result; adetermination of occupied may be considered a negative result. AListen-Before-Talk procedure (LBT) may comprise one or more CCAprocedure in an LBT time interval, for example with the same durationand/or same condition or threshold for positive result, or withdifferent durations and/or different conditions or thresholds. An LBTprocedure may be considered positive if a threshold number of CCAs ofthe LBT procedure are positive, for example each or half, and/or aminimum consecutive in time are positive. A positive LBT and/or CCAprocedure may allow access to the access target for transmission, forexample to be accessed within an access time interval. Access(permission to transmit) may be valid for a channel occupation time(COT); the maximum time of access may be a maximum COT (M-COT). The timeof access may be referred to as transmission duration (which may be aslong as the M-COT or shorter). A radio node like a wireless device doesnot have to transmit the whole M-COT after successful CCA/LBT. It may beconsidered that part of the M-COT is passed on to another device, whichthen may transmit (using the rest of the M-COT), e.g. upon and/or basedon suitable control signaling; this may be particularly useful in acentralised system. For example, in centralised system, a base stationmay initiate an access, transmit DL signaling to a wireless devicescheduled for UL transmission such that the wireless device transmitswithin the M-COT after the DL transmission has ended, e.g. due tosuitable scheduling information. The device performing successful accessto start transmission at the beginning of a M-COT or COT may beconsidered the device initiating a COT or M-COT. Depending on whetherthere is a gap between transmissions of different device, one or moreCCA procedures (in particular, shorter in total than for initiation) mayhave to be performed by the device taking over transmission. If a LBTprocedure was unsuccessful, a device may be required to backoff (e.g.,not trying to access for a backoff time interval, which may bepredefined or random). Accessing and/or transmitting on an access targetfrequency range may comprise on the whole bandwidth of the frequencyrange, or on part of it, for example interleaved and/or in a contiguouspart and/or utilising frequency hopping, and/or may be based onallocated and/or scheduled and/or configured resources, for example intime domain (e.g., for a number of symbols or a time interval) and/orfrequency domain (e.g., as in terms of frequency subranges and/orsubcarriers and/or PRBs and/or groups of PRBs assigned for transmission,e.g. allocated or scheduled or configured).

A transmission source may in particular comprise, and/or be representedby, and/or associated to, an antenna or group of antenna elements orantenna subarray or antenna array or transmission point or TRP or TP(Transmission Point) or access point. In some cases, a transmissionsource may be represented or representable, and/or correspond to, and/orassociated to, an antenna port or layer of transmission, e.g. formulti-layer transmission. Different transmission sources may inparticular comprise different and/or separately controllable antennaelement/s or (sub-)arrays and/or be associated to different antennaports and/or ports for reference signaling (e.g., such that referencesignaling on different ports is shifted relative to each other, e.g. incode domain and/or cyclic shift and/or frequency domain and/or timedomain, and/or is based and/or represents a different sequence root). Inparticular, analog beamforming may be used, with separate analog controlof the different transmission sources. An antenna port may indicate atransmission source, and/or a one or more transmission parameter, inparticular of reference signaling associated to the antenna port. Inparticular, transmission parameters pertaining to, and/or indicating afrequency domain distribution or mapping (e.g., which comb to use and/orwhich subcarrier or frequency offset to use, or similar) of modulationsymbols of the reference signaling, and/or to which cyclic shift to use(e.g., to shift elements of a modulation symbol sequence, or a rootsequence, or a sequence based on or derived from the root sequence)and/or to which cover code to use (e.g., (e.g., to shift elements of amodulation symbol sequence, or a root sequence, or a sequence based onor derived from the root sequence). In some cases, a transmission sourcemay represent a target for reception, e.g. if it is implemented as a TRPor AP (Access Point).

In the context of this disclosure, there may be distinguished betweendynamically scheduled or aperiodic transmission and/or configuration,and semi-static or semi-persistent or periodic transmission and/orconfiguration. The term “dynamic” or similar terms may generally pertainto configuration/transmission valid and/or scheduled and/or configuredfor (relatively) short timescales and/or a (e.g., predefined and/orconfigured and/or limited and/or definite) number of occurrences and/ortransmission timing structures, e.g. one or more transmission timingstructures like slots or slot aggregations, and/or for one or more(e.g., specific number) of transmission/occurrences. Dynamicconfiguration may be based on low-level signaling, e.g. controlsignaling on the physical layer and/or MAC layer, in particular in theform of DCI or SCI. Periodic/semi-static may pertain to longertimescales, e.g. several slots and/or more than one frame, and/or anon-defined number of occurrences, e.g., until a dynamic configurationcontradicts, or until a new periodic configuration arrives. A periodicor semi-static configuration may be based on, and/or be configured with,higher-layer signaling, in particular RCL layer signaling and/or RRCsignaling and/or MAC signaling.

In this disclosure, for purposes of explanation and not limitation,specific details are set forth (such as particular network functions,processes and signaling steps) in order to provide a thoroughunderstanding of the technique presented herein. It will be apparent toone skilled in the art that the present concepts and aspects may bepracticed in other variants and variants that depart from these specificdetails.

For example, the concepts and variants are partially described in thecontext of Long Term Evolution (LTE) or LTE-Advanced (LTE-A) or NewRadio mobile or wireless communications technologies; however, this doesnot rule out the use of the present concepts and aspects in connectionwith additional or alternative mobile communication technologies such asthe Global System for Mobile Communications (GSM) or IEEE standards asIEEE 802.11ad or IEEE 802.11 ay. While described variants may pertain tocertain Technical Specifications (TSs) of the Third GenerationPartnership Project (3GPP), it will be appreciated that the presentapproaches, concepts, and aspects could also be realized in connectionwith different Performance Management (PM) specifications.

Moreover, those skilled in the art will appreciate that the services,functions and steps explained herein may be implemented using softwarefunctioning in conjunction with a programmed microprocessor, or using anApplication Specific Integrated Circuit (ASIC), a Digital SignalProcessor (DSP), a Field Programmable Gate Array (FPGA) or generalpurpose computer. It will also be appreciated that while the variantsdescribed herein are elucidated in the context of methods and devices,the concepts and aspects presented herein may also be embodied in aprogram product as well as in a system comprising control circuitry,e.g. a computer processor and a memory coupled to the processor, whereinthe memory is encoded with one or more programs or program products thatexecute the services, functions and steps disclosed herein.

It is believed that the advantages of the aspects and variants presentedherein will be fully understood from the foregoing description, and itwill be apparent that various changes may be made in the form,constructions and arrangement of the exemplary aspects thereof withoutdeparting from the scope of the concepts and aspects described herein orwithout sacrificing all of its advantageous effects. The aspectspresented herein can be varied in many ways.

Some useful abbreviations comprise

Abbreviation Explanation ACK/NACK Acknowledgment/NegativeAcknowledgement ARQ Automatic Repeat reQuest BER Bit Error Rate BLERBlock Error Rate BPSK Binary Phase Shift Keying BWP Bandwidth Part CAZACConstant Amplitude Zero Cross Correlation CB Code Block CBG Code BlockGroup CDM Code Division Multiplex CM Cubic Metric CORESET ControlResource Set CP Cyclic Prefix CPE Common Phase Error CQI Channel QualityInformation CRC Cyclic Redundancy Check CRS Common reference signal CSIChannel State Information CSI-RS Channel state information referencesignal/ing CW Codeword, encoded and/or modulated information, e.g. in adata block DAI Downlink Assignment Indicator DCI Downlink ControlInformation DFT Discrete Fourier Transform DFTS-FDM DFT-spread-FDMDM(—)RS Demodulation reference signal(ing) eMBB enhanced MobileBroadBand EPRE Energy Per Resource Element FDD Frequency Division DuplexFDE Frequency Domain Equalisation FDF Frequency Domain Filtering FDMFrequency Division Multiplex FR1 Frequency Range 1, e.g. as specified byNR FR2 Frequency Range 2, e.g. as specified by NR HARQ Hybrid AutomaticRepeat Request IAB Integrated Access and Backhaul ICI Inter CarrierInterference IFFT Inverse Fast Fourier Transform IR Impulse Response ISIInter Symbol Interference MBB Mobile Broadband MCS Modulation and CodingScheme MIMO Multiple-input-multiple-output MRC Maximum-ratio combiningMRT Maximum-ratio transmission MU-MIMO Multiusermultiple-input-multiple-output NR 3GPP New Radio system NR-RS NRReference Signal (any type) OCC Orthogonal Cover Code OFDM/A OrthogonalFrequency Division Multiplex/Multiple Access PAPR Peak to Average PowerRatio PDCCH Physical Downlink Control Channel PDSCH Physical DownlinkShared Channel PN Phase Noise PRACH Physical Random Access CHannel PRBPhysical Resource Block (P)SCCH (Physical) Sidelink Control Channel PSDPower Spectral Density PSS Primary Synchronisation Signal(ing) (P)SSCH(Physical) Sidelink Shared Channel PTRS Phase Tracking RS PUCCH PhysicalUplink Control Channel PUSCH Physical Uplink Shared Channel QAMQuadrature Amplitude Modulation QPSK Quadrature Phase Shift Keying RANRadio Access Network RAT Radio Access Technology RB Resource Block RNTIRadio Network Temporary Identifier RRC Radio Resource Control RSReference Signal RSRP Received Signal Receive Power RSRQ Received SignalReceived Quality RX Receiver, Reception, Reception-related/side SAScheduling Assignment SC-FDE Single Carrier Frequency DomainEqualisation SC-FDM/A Single Carrier Frequency DivisionMultiplex/Multiple Access SCI Sidelink Control Information SINRSignal-to-interference-plus-noise ratio SIR Signal-to-interference ratioSNR Signal-to-noise-ratio SR Scheduling Request SRS Sounding ReferenceSignal(ing) SSS Secondary Synchronisation Signal(ing) SVD Singular-valuedecomposition TB Transport Block TCI Transmission ConfigurationIndicator TDD Time Division Duplex TDM Time Division Multiplex TRPTransmission Point, Transmission/Reception Point TRS Tracking RS TXTransmitter, Transmission, Transmission-related/side UCI Uplink ControlInformation UE User Equipment URLLC Ultra Low Latency High ReliabilityCommunication VL-MIMO Very-large multiple-input-multiple-output ZF ZeroForcing ZP Zero-Power, e.g. muted CSI-RS symbol

Abbreviations may be considered to follow 3G PP usage if applicable.

1. A method of operating a receiving radio node in a wirelesscommunication network, the method comprising: performing channelestimation based on received signaling, the channel estimation providinga channel estimate value for each subcarrier of a set of subcarriers;the received signaling covering a number NPRB of Physical ResourceBlocks, PRB, in frequency domain, each PRB having a number NSC ofsubcarriers; the set of subcarriers comprising a number NSUB of subsetsof subcarriers, subcarriers of the same subset being associated to thesame PRB of the number NPRB of PRBs; and the channel estimationassociating different channel estimate values to different subcarriersof one or more of the NSUB subsets.
 2. A receiving radio node for awireless communication network, the radio node configured to performchannel estimation based on received signaling; the channel estimationproviding a channel estimate value for each subcarrier of a set ofsubcarriers; the received signaling covering a number NPRB of PhysicalResource Blocks, PRB, in frequency domain, each PRB having a number NSCof subcarriers; the set of subcarriers comprising a number NSUB ofsubsets of subcarriers, subcarriers of the same subset being associatedto the same PRB of the number NPRB of PRBs; and the channel estimationassociating different channel estimate values to different subcarriersof one or more of the NSUB subsets.
 3. The method according to claim 1,wherein a channel estimate value associated to a subcarrier is based onprocessing over a number NRANGE of subcarriers of same subset of NSC orlower, in particular such that NSC/NRANGE=I, I being an integer.
 4. Themethod according to claim 1, wherein a channel estimate value associatedto a subcarrier is based on a filter applied to an environment of thesubcarrier, wherein the environment has a size of NRANGE subcarriers. 5.The method according to claim 1, wherein a channel estimate valueassociated to a subcarrier is based on at least one of averaging andweighing over an environment of the subcarrier, wherein the environmenthas a size of NRANGE subcarriers.
 6. The method according to claim 1,wherein the number of subcarriers associated to the same PRB in a subsetis smaller than NSC.
 7. The method according to claim 1, wherein achannel estimation is based on measurement on received signaling.
 8. Themethod according to claim 1, wherein the channel estimation is dependenton at least one of a carrier, a carrier frequency, a bandwidth, abandwidth part, a numerology, and a signaling characteristic associatedto the received signaling.
 9. The method according to claim 1, whereinprocessing over a range of subcarriers comprises at least one of:weighing one or more or all subcarriers in the range not carrying achannel estimate with zero; and disregarding such.
 10. A computerstorage medium storing a computer program comprising instructions thatwhen executed causes processing circuitry to at least one of control andperform a method, the method comprising: performing channel estimationbased on received signaling, the channel estimation providing a channelestimate value for each subcarrier of a set of subcarriers; the receivedsignaling covering a number NPRB of Physical Resource Blocks, PRB, infrequency domain, each PRB having a number NSC of subcarriers; the setof subcarriers comprising a number NSUB of subsets of subcarriers,subcarriers of the same subset being associated to the same PRB of thenumber NPRB of PRBs; and the channel estimation associating differentchannel estimate values to different subcarriers of one or more of theNSUB subsets.
 11. (canceled)
 12. The receiving radio node according toclaim 2, wherein a channel estimate value associated to a subcarrier isbased on processing over a number NRANGE of subcarriers of same subsetof NSC or lower, in particular such that NSC/NRANGE=I, I being aninteger.
 13. The receiving radio node according to claim 2, wherein achannel estimate value associated to a subcarrier is based on a filterapplied to an environment of the subcarrier, wherein the environment hasa size of NRANGE subcarriers.
 14. The receiving radio node according toclaim 2, wherein a channel estimate value associated to a subcarrier isbased on at least one of averaging and weighing over an environment ofthe subcarrier, wherein the environment has a size of NRANGEsubcarriers.
 15. The receiving radio node according to claim 2, whereinthe number of subcarriers associated to the same PRB in a subset issmaller than NSC.
 16. The receiving radio node according to claim 2,wherein a channel estimation is based on measurement on receivedsignaling
 17. The receiving radio node according to claim 2, wherein thechannel estimation is dependent on at least one of a carrier, a carrierfrequency, a bandwidth, a bandwidth part, a numerology, and a signalingcharacteristic associated to the received signaling.
 18. The receivingradio node according to claim 2, wherein processing over a range ofsubcarriers comprises at least one of: weighing one or more or allsubcarriers in the range not carrying a channel estimate with zero; anddisregarding such.
 19. The method according to claim 3, wherein I equalsone of 2, 3 and
 4. 20. The method according to claim 6, wherein PRB in asubset is smaller than one of NSC/2 or NSC/3 and NSC/4.
 21. The methodaccording to claim 7, wherein the measurement is at least one of signalstrength and signal quality.